Ask question

Ask question

All categories

3 years ago

15

What is the y intercept of the function f(x)=2 x 3^x

1 answer:

Lelechka [254]3 years ago

5 0

Answer:

(0,2)

Step-by-step explanation:

by substituting 0 for x you can find the y-intercept

f(x)=2*3^x

f(x)=2*3^0

f(x)=2*1

f(x)=2

You might be interested in

What was her heart rate one half hour after beginning the workout

n200080 [17]

Answer:

You need to post a picture.

5 0

3 years ago

A researcher wishes to estimate the percentage of adults who support abolishing the penny. What size sample should be obtained i

Scorpion4ik [409]

Answer:

a) We need a sample size of at least 3109.

b) We need a sample size of at least 4145.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

99% confidence level

So $\alpha = 0.01$ , z is the value of Z that has a pvalue of $1 - \frac{0.01}{2} = 0.995$ , so $Z = 2.575$ .

(a) he uses a previous estimate of 25%?

we need a sample of size at least n.

n is found when $M = 0.02, \pi = 0.25$ . So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.02 = 2.575\sqrt{\frac{0.25*0.75}{n}}$

$0.02\sqrt{n} = 2.575\sqrt{0.25*0.75}$

$\sqrt{n} = \frac{2.575\sqrt{0.25*0.75}}{0.02}$

$(\sqrt{n})^{2} = (\frac{2.575\sqrt{0.25*0.75}}{0.02})^{2}$

$n = 3108.1$

We need a sample size of at least 3109.

(b) he does not use any prior estimates?

When we do not use any prior estimate, we use $\pi = 0.5$

So

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.02 = 2.575\sqrt{\frac{0.5*0.5}{n}}$

$0.02\sqrt{n} = 2.575\sqrt{0.5*0.5}$

$\sqrt{n} = \frac{2.575\sqrt{0.5*0.5}}{0.02}$

$(\sqrt{n})^{2} = (\frac{2.575\sqrt{0.5*0.5}}{0.02})^{2}$

$n = 4144.1$

Rounding up

We need a sample size of at least 4145.

8 0

3 years ago

What is the domain and range for the function f(x) = x2 + 4x - 21?

bezimeni [28]

Answer:

Domain: (−∞,∞),{x|x∈R}

Range: [−25,∞),{y|y≥−25}

3 0

3 years ago

Chan wants to buy a used car that costs $8,500. He took out a loan for the cost of the car, and his payments are $209 per month

timama [110]

He would have paid about $1,532 dallors for the car after 4 years than the original price he has to pay for the monthly pay for the car.

4 0

3 years ago

Evaluate the integral by interpreting it in terms of areas. In other words, draw a picture of the region the integral represents

Oduvanchick [21]

Please find attached

thank you

3 0

3 years ago