We use it to substitute an unknown number. We have a variable for a number we don’t know and as we solve the problem we can find the answer for the variable or unknown number.

Step-by-step explanation:

I hope it helps! Have a great day!
Anygays-

8 0

2 years ago

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Use demoivre's theorem to show that;<br>cos4¤ =8 cos4¤ -8cos2¤+1

ss7ja [257]

Answer:

$\cos4( \theta)=Re(\cos4( \theta)+i\sin4( \theta)) \\=Re(\cos ( \theta)+i\sin ( \theta))^4 \\ =Re(cos^4( \theta)+4cos^3( \theta)isin( \theta)+6cos^2( \theta)i^2sin^2( \theta)+4cosi^3( \theta)sin^3( \theta)+i^4sin^4( \theta)) \\cos( 4\theta) =cos^4( \theta)-6cos^2( \theta)sin^2( \theta)+sin^4( \theta) \\ =(1-\sin^2( \theta))^2-6(1-\sin^2( \theta))\sin^2( \theta)+sin^4( \theta) \\ = 1-2\sin^2( \theta)+\sin^4( \theta)-6\sin^2( \theta)+6\sin^4( \theta)+\sin^4( \theta) \\ =8\sin^4( \theta)-8\sin^2( \theta)+1$

7 0

3 years ago

Which equation is represented by the line

gulaghasi [49]

Answer:

First, we need to find the slope of this line.

Slope is defined as rise over run, or change in y over change in x. We find two points on this line, and see that the slope is -4.

Then, we find the y-intercept, which in this case is 0.

Using slope intercept form, our answer is y=-4x

Let me know if this helps!

8 0

3 years ago

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