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2 years ago

If Y is directly proportional to X² and y=21 when x=2, find the value of y when X=4.

Mathematics

2 answers:

kykrilka [37]2 years ago

8 0

Step-by-step explanation:

it means y/x^2=k

when y=21, x=2; k is 21/4.

when x=4, k is y/16.

k=21/4=y/16.

the next step is easy to see, you can do it.

frozen [14]2 years ago

7 0

The value of y will probably be 4.

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Square root of 112p^2

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Answer:

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Step-by-step explanation:

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2 years ago

Which of the following constants can be added to x2 + x to form a perfect square trinomial? a.1/9 b.4/9 c.4 1/9

xenn [34]

You can add 4/9.

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3 years ago

If the local linear approximation of f(x) = 2cos x + e^2x at x = 2 is used to find the approximation for f(2.1), then the % erro

yKpoI14uk [10]

<u>Answer-</u>

The % error of this approximation is 1.64%

<u>Solution-</u>

Here,

$\Rightarrow f(x) = 2\cos x + e^{2x}$

$\Rightarrow f'(x) = -2\sin x + 2e^{2x}$

And,

$\Rightarrow f(2) = 2\cos 2 + e^{4}$

$\Rightarrow f'(2) = -2\sin 2 + 2e^{4}$

Taking (2, f(2)) as a point and slope as, f'(2), the function would be,

$\Rightarrow y-y_1=m(x-x_1)$

$\Rightarrow y-(2\cos 2 + e^{4})=(-2\sin 2 + 2e^{4})(x-2)$

$\Rightarrow y=(-2\sin 2 + 2e^{4})(x-2)+(2\cos 2 + e^{4})$

The value of f(2.1) will be

$\Rightarrow y=(-2\sin 2 + 2e^{4})(2.1-2)+(2\cos 2 + e^{4})$

$\Rightarrow y=(-2\sin 2 + 2e^{4})(0.1)+(2\cos 2 + e^{4})$

$\Rightarrow y=64.5946$

According to given function, f(2.1) will be,

$\Rightarrow f(2.1) = 2\cos 2.1 + e^{2(2.1)}$

$\Rightarrow f(2.1) = 65.6766$

$\therefore \%\ error=\dfrac{65.6766-64.5946}{65.6766}=0.0164=1.64\%$

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3 years ago

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gladu [14]

Answer:sadddddddddddddddddddddddddddddddddddddddddddddddddddd

Step-by-step explanation:

ddddddddddddddddddddddddddddddddddddddddddddddddddddddddd

3 0

2 years ago

Drag steps of the solution into order to solve for x in the equation 9(x + 3) = 108.

Marat540 [252]

Answer:

Given expression is,

9(x+3) = 108

In solving the equation the steps are as follows,

Step 1 : 9x + 27 = 108 ( By distributive property )

Step 2 : 9x = 81 ( Subtracting 108 on both sides )

Step 3 : x = 9 ( Divide both sides by 9)

Hence, by the above explanation we can drag the steps of solution in correct order.

3 0

3 years ago

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