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3 years ago

Given that f(x) = 7x^2 − 84 = 0, find x.

Mathematics

1 answer:

jasenka [17]3 years ago

8 0

Answer:

x = 3.464

Step-by-step explanation:

7x^2 - 84 = 0

7x^2 = 84

x^2 = 12

x= 3.464

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How to solve derivative of (sin3x)/x using first principle

Leona [35]

$\dfrac{d}{dx}(\dfrac{\sin(3x)}{x})$

First we must apply the Quotient rule that states,

$(\dfrac{f}{g})'=\dfrac{f'g-g'f}{g^2}$

This means that our derivative becomes,

$\dfrac{\dfrac{d}{dx}(\sin(3x))x-\dfrac{d}{dx}(x)\sin(3x)}{x^2}$

Now we need to calculate $\dfrac{d}{dx}(\sin(3x))$ and $\dfrac{d}{dx}(x)$

$\dfrac{d}{dx}(\sin(3x))=\cos(3x)\cdot3$

$\dfrac{d}{dx}(x)=1$

From here the new equation looks like,

$\dfrac{3x\cos(3x)-\sin(3x)}{x^2}$

And that is the final result.

Hope this helps.

r3t40

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2 years ago

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Buffy ate 100 fries in 5 minutes find her fry-eating rate in fries per minute

Paul [167]

Answer:

20 fries per minute.

Step-by-step explanation:

If you express the number of fries per minute as 100/5 (as there are 5 minutes and 100 fries), assuming she ate at the same rate per minute, she had 20 fries per minute.

To check, multiply 20 by 5, in order to find out her fries per 5 minutes. It should be equal to 100.

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2 years ago

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Drag statements and reasons to complete the proof

Rzqust [24]

Answer:

see below

Step-by-step explanation:

1) Slope from P to Q is F/E

2) Definition of slope

3) F'/E' = F/E

4 0

3 years ago

A submarine began a 120 feet below sea level and ascended at a rate of 13 feet per minute. What was the depth of the submarine a

Triss [41]

The submarine would be 900 below the ocean surface after 12 minutes assuming it started its descent at the surface of the ocean.

7 0

3 years ago

Determine the kinetic energy of 8000 Newton’s roller coaster car that is moving with a speed of 20.0 meters/seconds

ohaa [14]

Answer:

The kinetic energy of the roller coaster is 1600000 J.

Step-by-step explanation:

Given:

Mass of the roller coaster is 8000 Newton's and speed 20.0 meters/seconds.

Now, we need to find the kinetic energy $E_{k}$ of the roller coaster.

So, Mass of roller coaster (m) = 8000 N.

Velocity of roller coaster (v) = 20.0 m/s.

Now, putting the formula of kinetic energy:

$E_{k} = \frac{1}{2}\times m\times v^{2}$

$E_{k}=\frac{1}{2} \times 8000\times 20^{2}$

$E_{k}=\frac{1}{2} \times 8000\times 400$

$E_{k}=\frac{1}{2} \times 3200000$

$E_{k}=1600000$

Therefore, the kinetic energy of the roller coaster is 1600000 J.

3 0

3 years ago