The probability that the marble drawn from the bag will be either white or black is 2/3 or approximately 0.667.
To calculate this probability, we first need to find the total number of marbles in the bag, which is 10 + 20 + 5 = 35. Then, we need to find the total number of marbles that are either white or black, which is 10 + 20 = 30.
Finally, we divide the number of white or black marbles by the total number of marbles to get the probability:
30/35 = 2/3 ≈ 0.667
Therefore, the probability is approximately 0.667 or 2/3. This means that there is a higher chance of drawing a white or black marble than a grey marble, as there are more white and black marbles in the bag than grey marbles.
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Rewrite the expression in terms of sine and cosine and utilize the Fundamental Pythagorean Identity: sin²(x)+cos²(x)=1
Verify the identity using the Pythagorean Identity:
[tex]\frac{1-2cos^2(x)}{sin(x)cos(x)}=tan(x)-cot(x)[/tex]
The Fundamental Pythagorean Identity in trigonomety sin²(x)+cos²(x)=1
Using the Pythagorean Identity: [tex]\frac{1-2cos^2x}{sinxcosx}=tanx-cotx[/tex] ,
Hence prove.
Trigonometry formulas can be used to address many different kinds of issues. These issues could involve Pythagorean identities, product identities, trigonometric ratios (sin, cos, tan, sec, cosec, and cot), etc. Many formulas, such as those involving co-function identities (shifting angles), sum and difference identities, double angle identities, half-angle identities, etc., as well as the sign of ratios in various quadrants,
We know that the Pythagorean theorem,
sin²(x)+cos²(x)=1
We have
1-2cos²x = sin²(x)+cos²(x) -2cos²x
1-2cos²x = sin²(x)-cos²(x)
[tex]\frac{1-2cos^2x}{sinxcosx}=tanx-cotx[/tex]
To prove this take the right-hand sides
[tex]\frac{sin^2x}{sinxcosx}-\frac{cos^2x}{sinxcosx}\\\\=\frac{sinx}{cosx}-\frac{cosx}{sinx}\\\\= tanx-cotx[/tex]
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Lola has 4 1/2 cups of rice. She uses 3/4 of the rice to make sushi rolls for dinner. She uses the rest of the rice to make rice pudding for dessert. How much rice does Lola use for the rice pudding?
Based on the given information, Lola used 9/8 cups of rice for the rice pudding.
What is a fraction?A fraction is a mathematical expression that represents a part of a whole or a division of one quantity by another. It consists of two numbers separated by a horizontal line called a fraction bar or a vinculum. The number above the fraction bar is called the numerator, and the number below the fraction bar is called the denominator.
Lola has 4 1/2 cups of rice, which is equivalent to 9/2 cups of rice.
She uses 3/4 of the rice to make sushi rolls for dinner. So, the amount of rice she uses for the sushi rolls is:
(3/4) x (9/2) = 27/8 cups of rice
To find the amount of rice she uses for the rice pudding, we need to subtract the amount she used for the sushi rolls from the total amount she had:
9/2 - 27/8 = 36/8 - 27/8 = 9/8
So Lola used 9/8 cups of rice for the rice pudding.
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What is the result when the number 82 is increased by 50%?
Answer:
The answer is 41
Step-by-step explanation:
82 / 2
i need help on my practice test
The maximum point of this quadratic function f(t) = -16t² + 80t + 64 is equal to 164.
How to determine the maximum value of a quadratic equation?In this exercise, you are required to determine the maximum value of the given quadratic functions that is written in standard form. In Mathematics, the vertex form of a quadratic function is represented by the following mathematical equation:
y = a(x - h)² + k
Where:
h and k represents the vertex of the graph.a represents the leading coefficient.For the given quadratic function f(t) = -16t² + 80t + 64, the axis of symmetry can be calculated as follows:
Axis of symmetry, Xmax = -b/2a
Axis of symmetry, Xmax = -(80)/2(-16)
Axis of symmetry, Xmax = -80/-32
Axis of symmetry, Xmax = 2.5
For the vertex, we have:
f(t) = -16t² + 80t + 64
f(2.5) = -16(2.5)² + 80(2.5) + 64
f(2.5) = 164.
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The drama department of a school sold 679 tickets to the school play, for a total of $3370. Students paid $4 for a
ticket, and non-students paid $7.
a) Write a linear system for this equation.
b) How many non-students attended the play?
The linear equations are x + y = 679, 4x + 7y = 3370 and 586 non-students attended the play.
What is a linear equation, exactly?
A linear equation is a mathematical equation that describes a straight line when plotted on a graph. It is an equation in which the highest power of the variable is one. Linear equations are commonly written in the form of y = mx + b, where "x" and "y" are variables, "m" is the slope of the line, and "b" is the y-intercept. Linear equations can be used to model many real-world situations, such as distance and speed, cost and revenue, and temperature and time.
Now,
a) Let x = student tickets sold and y = number of non-student tickets sold. Then we have the following system of linear equations:
x + y = 679 (the total number of tickets sold is 679)
4x + 7y = 3370 (the total revenue from ticket sales is $3370)
b) To solve for y, we can use the first equation to get:
y = 679 - x
then,
4x + 7(679 - x) = 3370
Simplifying and solving for x, we get:
3x = 2363
x = 787
So 787 student tickets were sold. To find the number of non-student tickets sold, we can use the equation y = 679 - x:
y = 679 - 787 = -108
Since it doesn't make sense to have a negative number of non-student tickets sold, we made an error somewhere. Looking at the problem again, we realize that the equation should be:
x + y = 679 (the total number of tickets sold is 679)
4x + 7y = 3370 (the total revenue from ticket sales is $3370)
where y represents the number of student tickets sold and x represents the number of non-student tickets sold. With this correction, we get:
y = 679 - x
4(679 - x) + 7x = 3370
Simplifying and solving for x, we get:
3x = 1759
x = 586.33
x = 586
So 586 non-student tickets were sold.
Which means 586 non-students attended the play.
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A random sample of students at a middle school shows that 10 students prefer listening to rock, 15 students prefer listening to hip hop and 25 students prefer no music , while they exercise. is it biased or unbiased sample?
A random sample of students at a middle school shows that 10 students prefer listening to rock, 15 students prefer listening to hip hop and 25 students prefer no music, while they exercise. the given sample is unbiased.
Ten students at a middle school like to listen to rock, fifteen students prefer to listen to hip-hop, and twenty-five students prefer no music when they exercise.
The given sample is unbiased.
The term "biassed samples" refers to those that were created using biassed sampling methods. A biased sample is most likely not representative of the population. On the other hand, an "unbiased sample" is a sample that was created using a non-biased sampling method. An impartial sample is more likely to produce a representative sample. As was previously stated, a representative sample may not always be produced by an unbiased sampling technique, especially if the sample size is too small.
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a chair is normally $30.00. it's now on sale for 10% off. what is the sale price?
- ugly person
Answer:27
Step-by-step explanation:First you find 10% of 30 which is 3 then you subtract 30-3=27
Find the missing dimension of the prism.
Volume = 560 ft³
7 ft
U=
u
8 ft
ft
Answer:
u = 10ft
Step-by-step explanation:
7ft x 8ft = 56. 560 ÷ 56 = 10.
Therefore, u = 10ft
Which number should be added to
both sides of this quadratic equation
to complete the square?
The number that should be added to both sides of this quadratic equation to complete the square is (-3/2)² .
Explain about the completing square:When a square is complete, a quadratic is written in the shape of a squared bracket, and if necessary, a constant is added. Finding the function's highest or minimum value and the time it happens is one use for the square-root method.
We can solve quadratic equations that lack a factor by completing the square.
In order to make the left side of the formula a perfect square trinomial, the equation's form must be adjusted.
The given quadratic equation:
1 = x² - 3x
This can be written as:
x² - 3x - 1 = 0
a = 1, b = -3 and c = -1.
using the formula: (b/2)² = (-3/2)²
The number added both side is:
(-3/2)² + 1 = x² - 3x + (-3/2)² (required equation);
On simplification:
9/4 + 1 = (x -3/2)²
13/4 = (x -3/2)²
Thus, the number that should be added to both sides of this quadratic equation to completing square is (-3/2)² .
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which fraction are equivalent to 4/10? choose all the correct answers.
Answer: well it could be
2/5 or 8/20 or 1/5 or 16/40
Step-by-step explanation:
what is the area of the trapezoid?
Answer:
[tex] \ \frac{1}{2} (5 \frac{1}{4} + 7)(2) = 12 \frac{1}{4} [/tex]
A is correct.
as the size of a sample increases, the mean of the distribution of sample means increases always. (true/false). group of answer choices
As the size of a sample increases, the mean of the distribution of sample means increases always. - False
The mean of the distribution of sample means does not always rise as sample number rises. The population mean is not changed by increasing the sample number because the population mean is equivalent to the mean of the distribution of sample means. The variation of the distribution of the sample means does, however, decline as the sample number rises.
The distribution of sample means approximates normality with a mean equal to population mean and a standard deviation equal to population standard deviation divided by square base of the total sample size. This is known as the central limit theorem. As a result, the distribution of sample means becomes more tightly focused around the community mean and less variable as the sample number rises.
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How many lines of symmetry does the figure below have?
A) 0
B) 1
C) 2
D) 3
WILL GIVE BRAINLIEST TO THE CORRECT ANSWER
Find the value of x.
Let a = 10, b = 6, c = 12, and d = x
ab=cd
x = ab/c
x = 10(6)/12
x = 5
Pablo is mailing packages. Each small package costs him $2.80 to send. Each large package costs him $3.80. How much will it cost him to send 5 small packages and 4 large packages?
Step-by-step explanation & Answer
———-———-———-———-———-———-———-———-———-———-———-——
Page 1
So first we need to multiply the small packages by 5 because he needs to said 5 of them which is:
5 x 2.80 = 14 Which is our answer for the first part of the question.
Next we need to multiply the big/large packages by 4 because he is going to send 4 of them.
4 x 3.80 = 15.2 / ( money terms ) = 15.20
[tex]\left \{ {{small= 14} \atop {big=15.20}} \right.[/tex]
———-———-———-———-———-———-———-———-———-———-———-——
Page 2
We can them add them up or we can leave it at this but just in case lets add them up:
15.20 + 14 = 29.20 Which is the answer.
[tex]\left[\begin{array}{ccc}An&sw&r\\&=&\\22&.&9\end{array}\right][/tex]
Ms. Collins recently got an aquarium that is 3 ft tall, 3 feet wide, and 6 ft. long. She needs to fill her aquarium with water but she already put .5 ft of gravel in the bottom.
How much more room is left for the water?
There is 53.5 cubic feet of space left for water in the aquarium.
what is volume ?The volume of three-dimensional space occupied by an object or substance alone is referred to as volume.
The aquarium's total volume can be found by multiplying its dimensions:
Volume = Length x Width x Height
Volume = 6 ft x 3 ft x 3 ft
Volume = 54 cubic feet
However, Ms. Collins has already filled the bottom of the tank with gravel that takes up 0.5 ft of space. Therefore, the remaining space for water is:
Remaining space = Total volume - Gravel volume
Remaining space = 54 cubic feet - 0.5 cubic feet
Remaining space = 53.5 cubic feet
So, there is 53.5 cubic feet of space left for water in the aquarium.
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Use the graph to answer the question.
Determine the direction and degree of rotation used to create the image.
90 counterclockwise rotation
90 clockwise rotation
270 counterclockwise rotation
180 clockwise rotation
This represents the direction and degree of rotation utilised to make the image, which is 90 degrees anticlockwise.
what is degree of rotation ?When an item or form is rotated about a fixed point, generally the origin or a specified point in the plane, the amount of rotation that takes place is referred to as the degree of rotation. Angles are measured in degrees, where one full rotation equals 360 degrees. The amount of angle shift, expressed in degrees, that occurs when an item or shape is rotated is known as the degree of rotation. A shape has been turned a quarter of a full rotation anticlockwise, for instance, if it is rotated 90 degrees in that direction. Similar to this, a form has completed one-half of a full rotation if it is rotated 180 degrees.
given
The graph suggests that the image was rotated 90 degrees anticlockwise and in the other manner to make.
Compare the figure's initial placement (the grey triangle) to its final placement to see this (the red triangle).
One of the vertices on the grey triangle is pointing upward, and the other two are pointing to the right and left.
The red triangle's up-pointing vertex remains after the transformation, but the other two vertices now point down and up-left, respectively.
This represents the direction and degree of rotation utilised to make the image, which is 90 degrees anticlockwise.
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3n + 9 = 11n -23 Please
Answer: N=4
Step-by-step explanation:
Answer: n = 4
Step-by-step explanation:
subtract 9 from both sides simplify subtract 11n from both sides then combine like terms, simplify, divide both sides by the same factor, then simplify then boom :)
Find the approximate area of the lake whose shape is overlaid on the grid below. Each
square of the grid represents one square mile. (3 points)
Thus, the approximate area of lake whose shape is taken on the square of the grid is 8 sq. unit.
Explain about the area on grid:A grid area is a rectangular area just on grid that is made up of one or more grid cells. When you define an area using named grid areas or when you place an object using line-based placement, grid areas are produced.
By dividing the supplied figure in square grids and counting how many of these there are, it is easiest to determine the area of a typical two-dimensional shape.
For the following question:
The area of 1 complete grid is taken 1 sq. unit.Area greater than half but less then 1 is taken as 1/2 sq. unit.Area less than half units is not taken:Thus,
Total area = 4*1 + 8*(1/2)
Total area = 4 + 4
Total area = 8 sq. unit
Thus, the approximate area of the lake whose shape is taken on the square of the grid is 8 sq. unit.
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f we design a study to have no more than a 10% chance of a type 2 error, then the statistical power of the study equals 90%. true or false?
The statement " if we design a study to have no more than a 10% chance of a type 2 error, then the statistical power of the study equals 90%" is true because achieving a 10% chance of a type 2 error, or a 90% power, means that the study has a high probability of detecting a true effect if it exists
Statistical power is defined as the probability of correctly rejecting a false null hypothesis, or in other words, the probability of detecting a true effect if it exists. A type 2 error, on the other hand, occurs when we fail to reject a false null hypothesis, or when we fail to detect a true effect that actually exists.
Therefore, if we design a study to have no more than a 10% chance of a type 2 error (i.e., 90% power), then we are saying that the probability of detecting a true effect, if it exists, is 90%. This is equivalent to saying that the study has 90% power to detect the effect.
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The tree diagram shows the sample space of two digit numbers that can be created using the digits6, 5, 1, 7, what is the probability of choosing a number from the sample space that contains both 5 and 7.
Probability is a branch of mathematics that deals with the likelihood or chance of an event occurring, expressed as a number between 0 and 1. It is used to analyze and quantify the uncertainty associated with random events or processes.
what is the probability of choosing a number from the sample space that contains both 5 and 7?To find the probability of choosing a number from the sample space that contains both 5 and 7, we need to count the number of outcomes that satisfy this condition and divide by the total number of possible outcomes in the sample space.
From the tree diagram, we can see that there are four possible two-digit numbers that contain both 5 and 7: 57, 75, 56, and 65.
The total number of possible outcomes in the sample space is the number of ways to arrange the four digits in a two-digit number, which is 4 × 3 = 12 (since there are 4 choices for the first digit and 3 choices for the second digit, once the first digit is chosen).
Therefore, the probability of choosing a number from the sample space that contains both 5 and 7 is:
4/12 = 1/3
So the probability of choosing a number from the sample space that contains both 5 and 7 is 1/3 or approximately 0.33.
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Each serving of fruit punch that Will makes has 23
cup of pineapple juice and 12
cup of cranberry juice.
How many cups of fruit punch are in 16 servings?
1357
cups
1823
cups
2013
cups
24
cups
The total amount of juice in 16 servings is 2/3 + 1/3 = 1 cup, so the total amount of juice is 16 x 1 = 16 cups. This means there are 16 cups of fruit punch in 16 servings.
How many cups of fruit punch are in 16 servings?This question shows how to calculate the total quantity of a combination by multiplying the amount of each component by its respective ratio and then combining them together. It also emphasizes the need of understanding ratios and unit conversions while preparing recipes and measuring food.
To determine how many cups of fruit punch are in 16 servings, multiply the total amount of juice in 16 servings by 16.
For each serving, there are 2/3 cup of pineapple juice and 1/3 cup of cranberry juice, so the total amount of juice in each serving is:
2/3 + 1/3 = 1 cup
Therefore, the total amount of juice in 16 servings is:
16 x 1 = 16 cups
So there are 16 cups of fruit punch in 16 servings.
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Find the angle between the given vectors to the nearest tenth of a degree
U= (4,-8) V= (-6, -3)
Answer:
90°
Step-by-step explanation:
Given the vectors:
[tex]\displaystyle{\vec v = \langle -6, -3\rangle \ \: \text{and} \ \: \vec u = \langle 4, -8 \rangle}[/tex]
You can find the angle between two vectors by solving for θ in the equation:
[tex]\displaystyle{\vec v \times \vec u = |\vec v | |\vec u| \cos \theta}[/tex]
Where:
[tex]\displaystyle{\vec v \times \vec u = v_xu_x + v_yu_y}\\\\\displaystyle{|\vec v| = \sqrt{v_x^2 + v_y^2}}\\\\\displaystyle{|\vec u| = \sqrt{u_x^2+u_y^2}}[/tex]
Therefore:
[tex]\displaystyle{\vec v \times \vec u = |\vec v | |\vec u| \cos \theta}\\\\\displaystyle{(-6)(4)+(-3)(-8) = \sqrt{(-6)^2+(-3)^2} \cdot \sqrt{4^2+(-8)^2} \cos \theta}\\\\\displaystyle{-24+24=\sqrt{36+9}\cdot \sqrt{16+64}\cos \theta}\\\\\displaystyle{0=\sqrt{45}\cdot \sqrt{80}\cos \theta}\\\\\displaystyle{\dfrac{0}{\sqrt{45}\cdot \sqrt{80}}=\cos \theta}\\\\\displaystyle{0=\cos \theta}\\\\\displaystyle{\theta = 90^{\circ}}[/tex]
Therefore, the angle between two vectors is 90 degrees.
the daily high temperature in a town in Alaska has been colder than -4f for three weeks
This statement implies that the daily high temperature in the town in Alaska has been below -4°F (minus four degrees Fahrenheit) for three consecutive weeks.
A farmer is painting a new barn. He will need to calculate the surface area of the barn to purchase the correct amount of paint. In which of the following units can the farmer expect to calculate the surface area?
a) m
b) m²
c) ft
d) ft³
The farmer can expect to calculate the surface area of the barn in units of m² or square meters. Thus, option B is correct.
What is the surface area?Surface area is a two-dimensional measurement that represents the total area of all the faces or sides of a three-dimensional object. It is the sum of the areas of all the faces or surfaces that make up the object.
The surface area is typically expressed in square units, such as square meters (m²), square feet (ft²), or square centimetres (cm²), depending on the unit system used.
For example, the surface area of a cube with sides of length "s" can be calculated by finding the area of each face (which is s²), and then summing the areas:
Surface area of a cube = 6 x (side length)² = [tex]6s^2[/tex]
The farmer can expect to calculate the surface area of the barn in units of m² or square meters.
Surface area is a two-dimensional measurement that represents the total area of all the faces or sides of a three-dimensional object, such as a barn. The unit of measurement for surface area is always expressed in square units, such as m², ft², cm², etc.
Therefore, options (a) m, (c) ft, and (d) ft³ are incorrect, surface area
the farmer expect to calculate the surface area in [tex]m^2[/tex].
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Which of the following is a valid application of the distributive property?
A. 5 x 2 + 3 = 5 X (2 + 3)
B. 5 x 2 + 3 = 5 x (2) + 5 x (3)
B only
A only
Neither A nor B
Both A and B
Answer:
B only
Step-by-step explanation:
The correct answer is B only.
The distributive property states that a multiplication of a number by a sum or difference can be rewritten as the sum or difference of the products of the number with each term in the sum or difference. In other words, a(b + c) = ab + ac and a(b - c) = ab - ac.
Option A, 5 x 2 + 3 = 5 X (2 + 3), does not use the distributive property correctly. It tries to distribute the 5 over the sum 2 + 3, which is not possible.
Option B, 5 x 2 + 3 = 5 x (2) + 5 x (3), correctly applies the distributive property by distributing the 5 over each term in the sum 2 + 3.
Therefore, the valid application of the distributive property is B only.
What is the result when the number 94 is decreased by 50%?
Answer:
47
Step-by-step explanation:
Given: 94 decreased by 50%
First, we will change the percentage to a decimal, by moving the decimal two nodes to the left.
50% = .50
Next, we will multiply the decimal with the number.
94 · .50 = 47
check attached image for further explanation
Need helps with this too.
The radius and volume of the cylinder are 4 cm and 754 cm³ respectively and volume of the cone is 216 cm³.
What the volume of a cone and cylinder?
Volume of cone and cylinder is V = (1/3)πr²h and V = (1/3)πr²h respectively
where r is the radius of the base of the cone, h is the height of the cone, and π is the mathematical constant π (approximately equal to 3.14).
For cone:
To use this formula, we first need to find the radius of the base of the cone. We know that the diameter of the base is 12 cm, so the radius is half of that:
r = d/2 = 12/2 = 6 cm
Now we can plug in the values we have into the formula:
[tex]V = \frac{1}{3} \pi {r}^{2} h \\ V = \frac{1}{3} π( {6}^{2} )(19) \\ V = ( \frac{1}{3} )π(36)(19) \\ V = ( \frac{1}{3} )(3.14)(36)(19) \\ V = 216.24 cm³[/tex]
So, volume of the cone is 216.24 cm³ or 216 cm³ ( approximately)
For cylinder:
We are given the diameter of the cylinder as 8 cm, so we can find the radius as half of that:
r = d/2 = 8/2 = 4 cm
We are also given the height of the cylinder as 15 cm.
Now we can plug in these values into the formula:
[tex]V = π {r}^{2} h\\ V = π( {4}^{2} )(15) \\ V = π(16)(15) \\ V = 240π \\ V ≈ 753.98 \: cubic \: centimeters[/tex]
Therefore, the volume of the cylinder is approximately 753.98 cubic centimeters or 754 cm³ (approximately).
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Rewrite the expression in terms of sine and cosine and utilize the Fundamental Pythagorean Identity: sin²(x)+cos²(x)=1
Verify the identity using the Pythagorean Identity:
[tex]\frac{1-cos(x)}{sin(x)}=\frac{sin(x)}{1+cos(x)}[/tex]
The identity using the Pythagorean Identity:
[tex]\frac{1-cosx}{sinx}=\frac{sinx}{1+cosx}[/tex] , Hence proved
Trigonometry formulas can be used to address many different kinds of issues. These issues could involve Pythagorean identities, product identities, trigonometric ratios (sin, cos, tan, sec, cosec, and cot), etc. Many formulas, such as those involving co-function identities (shifting angles), sum and difference identities, double angle identities, half-angle identities, etc., as well as the sign of ratios in various quadrants,
the Fundamental Pythagorean Identity: sin²(x)+cos²(x)=1
Verify the identity using the Pythagorean Identity:
[tex]\frac{1-cosx}{sinx}=\frac{sinx}{1+cosx}[/tex]
To prove this take the right-hand side of the given identity.
We know that,
[tex]\frac{sinx}{1+cosx}*\frac{1-cosx}{1-cosx}\\\\=\frac{Sinx(1-cosx)}{1-cos^2x}\\\\=\frac{1-cosx}{sinx}[/tex]
Hence the left-hand sides.
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formula to find area of acircle
A = π r² is the formula
r is the radius
Hope it helps ✨
Answer:
Step-by-step explanation:
[tex]A=\pi \times r^2[/tex] where r is the circle's radius