Answers
Answer:
[tex] \alpha = \frac{ - b + \sqrt{ {b}^{2} - 4ac} }{2a} \\ \beta= \frac{ - b - \sqrt{ {b}^{2} - 4ac} }{2a} \\ \alpha +\beta = \frac{ - b + \sqrt{ {b}^{2} - 4ac} }{2a} + \frac{ - b - \sqrt{ {b}^{2} - 4ac} }{2a} \\ = \frac{ - 2b + 0}{2a} = \frac{ - 2b}{2a} \\ \therefore \: \alpha +\beta = - \frac{b}{a} \\ \alpha \times \beta = \frac{ - b + \sqrt{ {b}^{2} - 4ac} }{2a} \times \frac{ - b - \sqrt{ {b}^{2} - 4ac} }{2a} \\ = \frac{ {b}^{2} - ( {b}^{2} - 4ac) }{4 {a}^{2} } \\ = \frac{4ac}{4 {a}^{2} } \\ \therefore \alpha \times \beta = \frac{c}{a} \\ (x - \alpha)(x - \beta) = 0 \\ {x }^{2} + (\alpha + \beta)x + \alpha\beta = 0\\\\Let \:D =\sqrt{ {b}^{2} - 4ac}\\ If \:D >0 \Rightarrow \alpha, \beta \in \mathbb R\:(2 \: real \:roots)\\ If D =0 \Rightarrow \alpha= \beta \in \mathbb R\: (one \:real\: root) \\ If D <0 \Rightarrow \alpha, \beta \in \mathbb C\:(complex\: roots)\\At least 4examples\\{(x-1)}^{2}=0\\{x}^{2}-x-1=0 \\{x}^{2}-2x+13=0\\7{x}^{2}-49x-7=0\\ Applications\\ut+g{t}^{2}=s\\a=g\\u=-\frac{b}{a}\\s=\frac{c}{a}[/tex]
Answer:
Step-by-step explanation:
1) Determining the nature of roots:
Quadratic equation: ax² + bx +c = 0
Find D (Discriminant) using the D = b² - 4ac
If D = 0 , then the two roots are equal.
If D > 0, then the equation has two distinct real roots.
If D < 0, then the roots are complex/ imaginary.
One can find the sum and product of the roots using the below mentioned formula.
1) sum of roots = [tex]\frac{-b}{a}[/tex]
2) Product of roots = [tex]\frac{c}{a}[/tex]
If sum and product of the roots are given, one can frame the quadratic equation by x² - (sum of roots)*x + product of roots = 0
2) i) x² - 6x + 9 = 0
a = 1 ; b = -6 and c = 9
D = (-6)² - 4 * 1 * 9 = 36 - 36 = 0
D = 0. So, two equal roots
ii) x² - 4x + 3 = 0
a = 1 ; b = -4 ; c = 3
D = (-4)² - 4 * 1 * 3 = 16 - 12 = 4
D > 0. So, two distinct real roots.
iii) x² - 4x - 3 = 0
a = 1 ; b = -4 ; c = -3
D = (-4)² - 4*1*(-3) = 16 + 12 = 28 > 0
D > 0. So, two distinct real roots.
iv) x² - 4x + 7 = 0
a = 1 ; b = -4 ; c = 7
D =(-4)² - 4 *1 *7 = 16 - 28 = - 12
D< 0. So, two imaginary/ complex roots.
Related Questions
Animal populations are not capable of unrestricted growth because of limited habitat and food supplies. Under such conditions the population follows a logistic growth model: P(t) = d 1 + ke−ct where c, d, and k are positive constants. For a certain fish population in a small pond d = 1200, k = 11, c = 0.2, and t is measured in years. The fish were introduced into the pond at time t = 0. (a) How many fish were originally put in the pond? 100 Correct: Your answer is correct. fish (b) Find the population after 10, 20, and 30 years. (Round your answers to the nearest whole number.) 10 years 1 Changed: Your submitted answer was incorrect. Your current answer has not been submitted. fish 20 years fish 30 years fish (c) Evaluate P(t) for large values of t. What value does the population approach as t → [infinity]? P(t) =
Answers
Answer:
(a) 100 fishes
(b) t = 10: 483 fishes
t = 20: 999 fishes
t = 30: 1168 fishes
(c)
[tex]P(\infty) = 1200[/tex]
Step-by-step explanation:
Given
[tex]P(t) =\frac{d}{1+ke^-{ct}}[/tex]
[tex]d = 1200\\k = 11\\c=0.2[/tex]
Solving (a): Fishes at t = 0
This gives:
[tex]P(0) =\frac{1200}{1+11*e^-{0.2*0}}[/tex]
[tex]P(0) =\frac{1200}{1+11*e^-{0}}[/tex]
[tex]P(0) =\frac{1200}{1+11*1}[/tex]
[tex]P(0) =\frac{1200}{1+11}[/tex]
[tex]P(0) =\frac{1200}{12}[/tex]
[tex]P(0) = 100[/tex]
Solving (a): Fishes at t = 10, 20, 30
[tex]t = 10[/tex]
[tex]P(10) =\frac{1200}{1+11*e^-{0.2*10}} =\frac{1200}{1+11*e^-{2}}\\\\P(10) =\frac{1200}{1+11*0.135}=\frac{1200}{2.485}\\\\P(10) =483[/tex]
[tex]t = 20[/tex]
[tex]P(20) =\frac{1200}{1+11*e^-{0.2*20}} =\frac{1200}{1+11*e^-{4}}\\\\P(20) =\frac{1200}{1+11*0.0183}=\frac{1200}{1.2013}\\\\P(20) =999[/tex]
[tex]t = 30[/tex]
[tex]P(30) =\frac{1200}{1+11*e^-{0.2*30}} =\frac{1200}{1+11*e^-{6}}\\\\P(30) =\frac{1200}{1+11*0.00247}=\frac{1200}{1.0273}\\\\P(30) =1168[/tex]
Solving (c): [tex]\lim_{t \to \infty} P(t)[/tex]
In (b) above.
Notice that as t increases from 10 to 20 to 30, the values of [tex]e^{-ct}[/tex] decreases
This implies that:
[tex]{t \to \infty} = {e^{-ct} \to 0}[/tex]
So:
The value of P(t) for large values is:
[tex]P(\infty) = \frac{1200}{1 + 11 * 0}[/tex]
[tex]P(\infty) = \frac{1200}{1 + 0}[/tex]
[tex]P(\infty) = \frac{1200}{1}[/tex]
[tex]P(\infty) = 1200[/tex]
I keep looking and I can’t find the answer
Answers
Answer:
B
Step-by-step explanation:
sInce his average is equal or greater than league's average
I’m begging for someone to help me with this so bad it about in order largest to small et) (NO LINKS) (NO LYING) IT MUST BE THa. PART 3
Answers
Answer:
1) AM, MY, AY
2) GY, GQ, QY
3) QM, QG, MG
4) YX, YG, XG
Step-by-step explanation:
In triangles, the shortest side is always the side that is directly across from the smallest angle while the longest side is always the side that is directly across from the largest angle.
Using this concept, we can answer the questions;
1) Largest side = AM
Smallest side = AY
Arranging from largest to smallest side;
AM, MY, AY
2) Largest side = GY
Shortest side = QY
Arranging from largest to smallest side;
GY, GQ, QY
3) Largest side = QM
Shortest side = MG
Arranging from largest to smallest side;
QM, QG, MG
4) Largest side = YX
Smallest side = XG
Arranging from largest to smallest side;
YX, YG, XG
Which equation goes with the t-chart below?
Answers
Answer:
y = 2 x^2 + 5
Step-by-step explanation:
y = 2x^2 + 5
y = 2(-2)^2 + 5
y= 2(4) + 5
y = 8 + 5
y = 13
you can try for yourself using the other values
All of Jenny's pets are dogs except one. All of her pets are cats except one. How many cats and dogs does Jenny have?
NO LINKS OR U GET REPORTED!
Answers
divide 12 unto two parts such that
their product is 35
Answers
Plesse help me:) ive been stuck on this for a while
Answers
Answer:
4th number line (the one of the bottom right)
Step-by-step explanation:
First, solve the inequality, then choose the number line that mathes the solution.
3x ≤ -6
Only step: Divide by 3.
x ≤ -6/3
x ≤ -2
But which number line matches the solution?
We know this is going left, so #1 & #3 are out. This also has a closed circle (because of ≤ (less than/equal to)), so #2 is also out.
Number line #4 matches the solution (x ≤ -2), so it is the answer.
Answer please and explain
Answers
Answer:
C=84
Step-by-step explanation:
Since you use 3 for pi. You plug the radius into the formula. C=2×3x14=84
Solve for x using
cross multiplication.
3x - 3
2x – 2
=
5
4
x = [?]
Answers
Answer:
Step-by-step explanation:
Given
(3x - 3) / 5 = (2x - 2) / 4
Begin by cross multiplying
Solution
4(3x - 3) = 5(2x - 2) Use the distributive property to remove brackets12x - 12 = 10x - 10 Add 12 to both sides.12x = 10x - 10 + 12 Combine the right12x = 10x + 2 Subtract 10x from both sides12x-10x = 2 Combine the left2x = 2 Divide by 2x = 2/2x = 1Note: the original equation gives you 0/5 = 0/4 which is 0 = 0.
Polygon ABCDE has a vertex at A(-4, 2). If the polygon is translated 4 units right and 2 units up, what are the coordinates of A'?
Answers
Answer:
(0,4)
Step-by-step explanation:
Add 4 to x and add 2 to y.
HELPPPP ITS TIMEDDD WILL GIVE BRAINLYISTTTT
Answers
Can u guys help me pls ill give u 20 points
Answers
Answer:
Its either L or N im not sure but if i had to guess out of the two i think its L.
Step-by-step explanation:
IF PASSPORT is written as RCUURQTV, then how will BOOKLET be coded?
Answers
Answer: DQQMNGV
Step-by-step explanation: Each letter is shifted two letters to the right on a letter strip (a -> b -> c), so BOOKLET would be DQQMNGV.
Hope this helps!
A company that manufactures electronic components wants to know the mean discharge time of one particular type of capacitor that it makes. In order to estimate this value, they randomly select 100 capacitors and measure how long they take to discharge. The mean of this sample was 7.25 seconds with a standard deviation of 0.15 seconds. Assuming that this distribution is normal, construct a 99% confidence interval to estimate the mean discharge time for all capacitors of this type. Is this question asking for a confidence interval or hypothesis test
Answers
Answer:
99% confidence interval to estimate the mean discharge time for all capacitors of this type
(7.2146, 7.2854)
Step-by-step explanation:
Step(i):-
Given that the sample size 'n' = 100
Given that the mean of sample x⁻ = 7.25 seconds
Given that the standard deviation of the sample (S) = 0.15 seconds
Level of significance = 0.01
Degrees of freedom = n-1 =100-1 =99
t₀.₀₁ , ₉₉ = 2.3646
We have to find that the 99% of the confidence interval of the mean
Step(ii):-
99% confidence interval to estimate the mean discharge time for all capacitors
[tex](x^{-} - t_{0.01 , 99} \frac{S}{\sqrt{n} } , x^{-} + t_{0.01 , 99} \frac{S}{\sqrt{n} } )[/tex]
[tex](7.25 - 2.3646 \frac{0.15}{\sqrt{100} } , 7.25 + 2.3646 \frac{0.15}{\sqrt{100} } )[/tex]
(7.25 - 0.0354 , 7.25 + 0.0354)
(7.2146, 7.2854)
Final answer:-
99% confidence interval to estimate the mean discharge time for all capacitors of this type
(7.2146, 7.2854)
Help me I have this due today!!!
Answers
Answer:
The answer is 21/25.
Step-by-step explanation:
I hope this helps! Have a great rest of your day!
I need help asap please! 20 points!
Graph the parabola.
y=x²–2x-4
Plot five points on the parabola: the vertex, two points to the left of the vertex, and two points to the right of the vertex. Then click on the graph-a-function
button
Answers
This is the graph I hope this helps
HELP! WILL GIVE BRANLIEST!
Answers
Answer:
Step-by-step explanation:
z = 119 Vertically opposite angles are equal.
5x + 41 + 119 = 180 5x + 41 and 119 are supplementary.
4x + 160 = 180 Subtract 160 from both sides
4x = 180 - 160
4x = 20 Divide by 4
x = 20/4
x = 5
Nevaeh invested $660 in an account paying an interest rate of 3% compounded
continuously. Jonathan invested $660 in an account paying an interest rate of 3 %
compounded monthly. After 14 years, how much more money would Nevaeh have in
her account than Jonathan, to the nearest dollar?
Answers
Answer:
19
Step-by-step explanation:
Rate 1: 3
4
1
%=3+1/4=
\,\,3.25\%\rightarrow 0.0325
3.25%→0.0325
\text{Rate 2: }3\tfrac{1}{8}\%=3+1/8=
Rate 2: 3
8
1
%=3+1/8=
\,\,3.125\%\rightarrow 0.03125
3.125%→0.03125
\text{Calculate Final Amount for Nevaeh}
Calculate Final Amount for Nevaeh
\overline{\phantom{\text{Calculate Final Amount for Nevaeh}}}
Calculate Final Amount for Nevaeh
\text{Compounded Continuously:}
Compounded Continuously:
A=Pe^{rt}
A=Pe
rt
P=660\hspace{35px}r=0.0325\hspace{35px}t=14
P=660r=0.0325t=14
Given values
A=660e^{0.0325(14)}
A=660e
0.0325(14)
Plug in
A=660e^{0.455}
A=660e
0.455
Multiply
A=1040.2744
A=1040.2744
Use calculator (with e button)
\text{Calculate Final Amount for Jonathan}
Calculate Final Amount for Jonathan
\overline{\phantom{\text{Calculate Final Amount for Jonathan}}}
Calculate Final Amount for Jonathan
\text{Compounded Monthly:}
Compounded Monthly:
A=P\left(1+\frac{r}{n}\right)^{nt}
A=P(1+
n
r
)
nt
Compound interest formula
P=660\hspace{35px}r=0.03125\hspace{35px}t=14\hspace{35px}n=12
P=660r=0.03125t=14n=12
Given values
A=660\left(1+\frac{0.03125}{12}\right)^{12(14)}
A=660(1+
12
0.03125
)
12(14)
Plug in values
A=660(1.0026042)^{168}
A=660(1.0026042)
168
Simplify
A=1021.6468
A=1021.6468
Use calculator
\text{How much more money Nevaeh has:}
How much more money Nevaeh has:
1040.2744-1021.6468
1040.2744−1021.6468
18.6276
18.6276
\$ 19
$19
how many oz do you think this cup is
Answers
Answer:
I'm gonna say 12??
Step-by-step explanation:
Am I close?
Have a nice day! <3
Which equation represents the table of values
Answers
Answer:where the equations
Step-by-step explanation:
Which property of quadrilaterals inscribed in a circle can be used to find value of X in the figure below?
A. The difference between an opposite pair of angles 180°.
B. The difference between an opposite a pair of angles is 0°.
C. The some of an opposite pair of angles is 180°.
D. The sum of an opposite pair of angles is 360°.
Answers
Answer: that’s the answer c
Step-by-step explanation:
Bc of the work you put in
If g(x) = 8(1/2)^x then what is g(-1)= ?
Answers
Answer:
x=0
g−1(4)=0∵ g(0)=4
Step-by-step explanation:
Which is the correct formula to find the area of triangle AED?
Answers
Answer:
Area of triangle AED = [tex]\frac{1}{2}[/tex] × AE × DE
Step-by-step explanation:
The area of a triangle is [tex]\frac{bxh}{2}[/tex]
Answer:
Other person is right, i took the test
Step-by-step explanation:
5−3 when =−2,=4,=6 evaluate
Answers
Answer:
x = 2, -1
Step-by-step explanation:
Move all terms to the left side and set equal to zero Then set each factor equal to zero
Which of the following are solutions to the following equation?
4x^2-100=0.
Check all that apply.
A. 5
B. -10
C. -5
D. 10
Answers
Answer:x=5 or x=−5
Step-by-step explanation:
4x^2−100=0
Step 1: Add 100 to both sides.
4x^2−100+100=0+100
4x^2=100
Step 2: Divide both sides by 4.
4x^2/4=100/4
x^2=25
Step 3: Take square root.
x=±√25
x=5 or x=−5
Answer:
x=5 or x=−5
PLEASE HELPPO?!!!! Look at the attachment below
Answers
Answer:
157
Step-by-step explanation:
just trust me bro
In this experiment researchers randomly assigned smokers to treatments. Of the 193 smokers taking a placebo, 29 stopped smoking by the 8th day. Of the 266 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day. Calculate the estimated standard error for the sampling distribution of differences in sample proportions.
Answers
Answer:
The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.
Step-by-step explanation:
To solve this question, we need to understand the Central Limit Theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction of normal variables:
When we subtract normal variables, the mean is the subtraction of the means, while the standard error is the square root of the sum of the variances:
Of the 193 smokers taking a placebo, 29 stopped smoking by the 8th day.
This means that:
[tex]p_S = \frac{29}{193} = 0.1503[/tex]
[tex]s_S = \sqrt{\frac{0.1503*0.8497}{193}} = 0.0257[/tex]
Of the 266 smokers taking only the antidepressant buproprion, 82 stopped smoking by the 8th day.
This means that:
[tex]p_A = \frac{82}{266} = 0.3083[/tex]
[tex]s_A = \sqrt{\frac{0.3083*0.6917}{266}} = 0.0283[/tex]
Calculate the estimated standard error for the sampling distribution of differences in sample proportions.
[tex]s = \sqrt{s_S^2 + s_A^2} = \sqrt{0.0257^2 + 0.0283^2} = 0.0382[/tex]
The estimated standard error for the sampling distribution of differences in sample proportions is 0.0382.
When can you write ratios as a fraction?
Answers
Answer:
In a mathequation when needed
Step-by-step explanation:
What is the equation of the line shown in the graph at the right?
Answers
I need this please help me
Answers
Step-by-step explanation:
a. Josh Studies more after earnings Low Test score is
when Y = in 15 Score Josh Time to Studies are 0 Hours
b. There is no association Between hours studied & Test Score = Nope ...After Josh GOT much Time to Studies He Can Make 98 Scores with 7 Hours Time Studies and average data can show is josh average time in studies comparing to Hours his make much scores
c. There is Positive Association Between hours & Test Score Yes
d. Nope