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3 years ago

Write the expression in terms of sine only sin 9x cos 9x

Mathematics

1 answer:

Usimov [2.4K]3 years ago

6 0

$\sin 2\alpha= 2\sin \alpha\cos\alpha\quad\Rightarrow\quad\sin 9x\cos 9x=\frac{1}{2}\sin 18x$

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Anna [14]

Answer:

Option A. $10\ units^{2}$

Step-by-step explanation:

we know that

The area of the rectangle is equal to

A=LW

where

L is the length of rectangle

W is the width of rectangle

we have

$A(-3,1),B(-2,-1),C(2,1),D(1,3)$

Plot the vertices

see the attached figure

L=AD=BC

W=AB=DC

the formula to calculate the distance between two points is equal to

$d=\sqrt{(y2-y1)^{2}+(x2-x1)^{2}}$

Find the distance AD

$A(-3,1),D(1,3)$

substitute in the formula

$AD=\sqrt{(3-1)^{2}+(1+3)^{2}}$

$AD=\sqrt{(2)^{2}+(4)^{2}}$

$AD=\sqrt{20}$

$AD=2\sqrt{5}\ units$

Find the distance AB

$A(-3,1),B(-2,-1)$

substitute in the formula

$AB=\sqrt{(-1-1)^{2}+(-2+3)^{2}}$

$AB=\sqrt{(-2)^{2}+(1)^{2}}$

$AB=\sqrt{5}$

$AB=\sqrt{5}\ units$

Find the area

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Step-by-step explanation:

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Andre45 [30]

KX = x+4 so solve for k.
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Answer:

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Step-by-step explanation:

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ElenaW [278]

Answer:

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A. left

B. down

C. up

✓D. right

Right is the right answer.

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3 years ago

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