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Find the value of $sin(2x)$ and $cos(2x)$ on the unit circle

Answer 1

Abigail Nelson

Benjamin Clark

To find the value of $\sin(2x)$ and $\cos(2x)$ on the unit circle, we can utilize the double-angle formulas:

$ \sin(2x) = 2\sin(x)\cos(x) $

$ \cos(2x) = \cos^2(x) – \sin^2(x) $

Given a point on the unit circle (a, b) where $a = \cos(x)$ and $b = \sin(x)$, we can substitute:

$ \sin(2x) = 2ab $

$ \cos(2x) = a^2 – b^2 $

Answer 2

Alex Thompson

Isabella Walker

Using the double-angle identities, we find:

$ sin(2x) = 2sin(x)cos(x) $

$ cos(2x) = cos^2(x) – sin^2(x) $

For any point on the unit circle (a, b) where $a = cos(x)$ and $b = sin(x)$, we get:

$ sin(2x) = 2ab $

$ cos(2x) = a^2 – b^2 $

Answer 3

Amelia Mitchell

Michael Moore

Use the double-angle formulas:

$ sin(2x) = 2sin(x)cos(x) $

$ cos(2x) = cos^2(x) – sin^2(x) $