What is the vertex of the quadratic function below?

Let h(x)=20e^kx where k ɛ R (Picture attached. Thank you so much!)

zloy xaker [14]

Answer:

A)

$k=0$

B)

$\displaystyle \begin{aligned} 2k + 1& = 2\ln 20 + 1 \\ &\approx 2.3863\end{aligned}$

C)

$\displaystyle \begin{aligned} k - 3&= \ln \frac{1}{2} - 3 \\ &\approx-3.6931 \end{aligned}$

Step-by-step explanation:

We are given the function:

$\displaystyle h(x) = 20e^{kx} \text{ where } k \in \mathbb{R}$

A)

Given that h(1) = 20, we want to find k.

h(1) = 20 means that h(x) = 20 when x = 1. Substitute:

$\displaystyle (20) = 20e^{k(1)}$

Simplify:

$1= e^k$

Anything raised to zero (except for zero) is one. Therefore:

$k=0$

B)

Given that h(1) = 40, we want to find 2k + 1.

Likewise, this means that h(x) = 40 when x = 1. Substitute:

$\displaystyle (40) = 20e^{k(1)}$

Simplify:

$\displaystyle 2 = e^{k}$

We can take the natural log of both sides:

$\displaystyle \ln 2 = \underbrace{k\ln e}_{\ln a^b = b\ln a}$

By definition, ln(e) = 1. Hence:

$\displaystyle k = \ln 2$

Therefore:

$2k+1 = 2\ln 2+ 1 \approx 2.3863$

C)

Given that h(1) = 10, we want to find k - 3.

Again, this meas that h(x) = 10 when x = 1. Substitute:

$\displaystyle (10) = 20e^{k(1)}$

Simplfy:

$\displaystyle \frac{1}{2} = e^k$

Take the natural log of both sides:

$\displaystyle \ln \frac{1}{2} = k\ln e$

Therefore:

$\displaystyle k = \ln \frac{1}{2}$

Therefore:

$\displaystyle k - 3 = \ln\frac{1}{2} - 3\approx-3.6931$

3 0

2 years ago

Valerie runs track and field. At meets, Valerie lkes to buy protein bars, bananas and sports drinks Protein bars are $1. bananas

VladimirAG [237]

Complete Question

Valerie runs track and field. At meets, Valerie likes to buy protein bars, bananas, and sports drinks. Protein bars are $1, bananas are $0.50, and sports drinks are $2. Valerie has $10 to spend. She will spend no more than twice as much on sports drinks as bananas and at least three times as much on bananas as protein bars.

Let p represent the number of protein bars, b represent the number of bananas, and d represent the number of sports drinks that Valerie buys.

Which statements are true regarding Valerie's situation? Select all that apply A: p + 0.5b + 2d < 10 B: 0.5d + b + 3p < 10. C: d < 2b. D: b > 3p. E: 2d < b. F: 3b > p

Answer:

The statements that are true regarding Valerie's situation:

A: p + 0.5b + 2d < 10

C: d < 2b

D: b > 3p

Step-by-step explanation:

Lets represent

The number of protein bars as p.

The number of bananas as b.

The number of sports drinks that Valerie buys as d.

From the question:

We are told

Protein bars are $1

Bananas are $0.50

Sports drinks are $2.

She will spend no more than twice as much on sports drinks as bananas

d ≤ 2b = d < 2b

At least three times as much on bananas as protein bars.

b ≥ 3p = b > 3p

We are also told that:

Valerie has $10 to spend.

Hence:

$1 × p + $0.50 × b + $2 × d < $10

= p + 0.5b + 2d < 10

Therefore, the statements that are true regarding Valerie's situation:

A: p + 0.5b + 2d < 10

C: d < 2b

D: b > 3p

5 0

3 years ago

Kaitlin is on a long car trip. Everytime she stops for gas she loses 15 minutes of travel time. If she has to stop fives times h

Nastasia [14]

She will be 75 minutes late because you take the 15 minutes per stop and multiply it by the five stops.

7 0

3 years ago

Read 2 more answers

I really need your help . And don’t worry this is just a practice :)

MariettaO [177]

Answer:

65/80 score

Step-by-step explanation:

3 0

3 years ago

2. Neil's airplane needs a full tank of fuel

Alenkinab [10]

It’s tc ccgvchvg gyvCyzbzugs if htkgin to be even

3 0

3 years ago