This equation shows how the amount of money Sadie makes from selling lemonade is related to the number of cups sold. d =3c

A bag contains 5 blue marbles, 6 red marbles, and 7 green marbles. two random marbles are drawn, one at a time without replaceme

SSSSS [86.1K]

The probability of you drawing two red marbles in a row is 1:3

5 0

3 years ago

The Fibonacci sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, … is formed by summing two consecutive numbers to get the next number.

adelina 88 [10]

By counting the combinations, we will see that there are 10 combinations such that the sum gives a Fibonacci number.

<h3>How to count the combinations?</h3>

We have two number cubes with 6 outcomes each, such that we have a total of 36 combined outcomes.

For each dice, the outcomes are:

{1, 2, 3, 5, 8, 13}

Now, let's count the combinations that also give a Fibonacci number (these are given by adding two consecutive numbers in the sequence).

I will list each possible red outcome, then the blue outcomes that would give a Fibonacci term, and then we can count the number of combinations.

Red Blue number of combinations.
1 2 1
2 1, 2 2
3 2, 3 2
5 3, 8 2
8 5, 13 2
13 8 1

Adding the numbers of combinations, we have:

C = 1 + 2 + 2 + 2 + 2 + 1 = 10

There are 10 combinations that give a Fubbonaci number.

If you want to learn more about combinations, you can read:

brainly.com/question/2280026

8 0

2 years ago

How to find the derivative of cos^2x? i seem to be confused.

slamgirl [31]

If you're using the app, try seeing this answer through your browser: brainly.com/question/2927231

————————

You can actually use either the product rule or the chain rule for this one. Observe:

• Method I:

y = cos² x

y = cos x · cos x

Differentiate it by applying the product rule:

$\mathsf{\dfrac{dy}{dx}=\dfrac{d}{dx}(cos\,x\cdot cos\,x)}\\\\\\
\mathsf{\dfrac{dy}{dx}=\dfrac{d}{dx}(cos\,x)\cdot cos\,x+cos\,x\cdot \dfrac{d}{dx}(cos\,x)}$

The derivative of cos x is – sin x. So you have

$\mathsf{\dfrac{dy}{dx}=(-sin\,x)\cdot cos\,x+cos\,x\cdot (-sin\,x)}\\\\\\
\mathsf{\dfrac{dy}{dx}=-sin\,x\cdot cos\,x-cos\,x\cdot sin\,x}$

$\therefore~~\boxed{\begin{array}{c}\mathsf{\dfrac{dy}{dx}=-2\,sin\,x\cdot cos\,x}\end{array}}\qquad\quad\checkmark$

—————

• Method II:

You can also treat y as a composite function:

$\left\{\!
\begin{array}{l}
\mathsf{y=u^2}\\\\
\mathsf{u=cos\,x}
\end{array}
\right.$

and then, differentiate y by applying the chain rule:

$\mathsf{\dfrac{dy}{dx}=\dfrac{dy}{du}\cdot \dfrac{du}{dx}}\\\\\\
\mathsf{\dfrac{dy}{dx}=\dfrac{d}{du}(u^2)\cdot \dfrac{d}{dx}(cos\,x)}$

For that first derivative with respect to u, just use the power rule, then you have

$\mathsf{\dfrac{dy}{dx}=2u^{2-1}\cdot \dfrac{d}{dx}(cos\,x)}\\\\\\
\mathsf{\dfrac{dy}{dx}=2u\cdot (-sin\,x)\qquad\quad (but~~u=cos\,x)}\\\\\\
\mathsf{\dfrac{dy}{dx}=2\,cos\,x\cdot (-sin\,x)}$

and then you get the same answer:

$\therefore~~\boxed{\begin{array}{c}\mathsf{\dfrac{dy}{dx}=-2\,sin\,x\cdot cos\,x}\end{array}}\qquad\quad\checkmark$

I hope this helps. =)

Tags: <em>derivative chain rule product rule composite function trigonometric trig squared cosine cos differential integral calculus</em>

3 0

3 years ago

Can somebody please help me with this question and provide an explanation?

SSSSS [86.1K]

Answer:

first of all the formula

y = mx+c

where m is slope and c is y-intercept.

now substitute the values-

y = 2x - 5

(for the slope here is 2 and the part where the line intercepts y axis is -5

therefore

y = 2x-5

7 0

2 years ago

Read 2 more answers

Fiona recorded the mean math exam grade for six random samples of students from the entire seventh-grade class. Sample Sample Me

Charra [1.4K]

The reason why Fiona cannot make a valid prediction based on the mean of the population is that the variation of Fiona’s samples is too large.

<h3>Why can't Fiona use the means she recorded?</h3><h3 />

Mean is quite sensitive to outliers so it is best used when the variation between variables is not too much.

In Fiona's case, there variation is quite high with high variable of 95 compared to a low value of 45.

Find out more on effect of outliers at brainly.com/question/16815987.

#SPJ1

7 0

2 years ago