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Given a point on the unit circle, find its cosine and sine values.

Answer 1

Abigail Nelson

Sophia Williams

Given a point \((\cos\theta, \sin\theta)\) on the unit circle, determine the coordinates when \(\theta = \frac{\pi}{4}\).

The unit circle has a radius of 1. At \(\theta = \frac{\pi}{4}\), both x and y coordinates are equal:

$\cos\frac{\pi}{4} = \sin\frac{\pi}{4} = \frac{\sqrt{2}}{2}$

Therefore, the coordinates are:

$(\cos\frac{\pi}{4}, \sin\frac{\pi}{4}) = \left(\frac{\sqrt{2}}{2}, \frac{\sqrt{2}}{2}\right)$

Answer 2

Alex Thompson

Isabella Walker

Given a point ((cos heta, sin heta)) on the unit circle, find the coordinates for ( heta = frac{5pi}{6}).

For ( heta = frac{5pi}{6}), we use reference angle (frac{pi}{6}) and quadrant considerations:

$cosfrac{pi}{6} = frac{sqrt{3}}{2}$ and $sinfrac{pi}{6} = frac{1}{2}$

Since (frac{5pi}{6}) is in the second quadrant,

$cosfrac{5pi}{6} = -frac{sqrt{3}}{2}$ and $sinfrac{5pi}{6} = frac{1}{2}$

Therefore, the coordinates are:

$(cosfrac{5pi}{6}, sinfrac{5pi}{6}) = left(-frac{sqrt{3}}{2}, frac{1}{2}
ight)$

Answer 3

Amelia Mitchell

Michael Moore

Given a point ((cos heta, sin heta)) on the unit circle, compute the coordinates for ( heta = frac{3pi}{2}).

At ( heta = frac{3pi}{2}), the coordinates are:

$cosfrac{3pi}{2} = 0$ and $sinfrac{3pi}{2} = -1$

Therefore, the coordinates are:

$(cosfrac{3pi}{2}, sinfrac{3pi}{2}) = (0, -1)$