Question

Find an exact value.\\ $\cos\frac{-7\pi}{12}$\\ A) $\frac{\sqrt{2}-\sqrt{6}}{4}$\\ B) $\sqrt{2}-\sqrt{6}$\\ C) $\sqrt{6}+\sqrt{2}$\\ D) $\frac{\sqrt{6}-\sqrt{2}}{4}$

          Find an exact value.\\
$\cos\frac{-7\pi}{12}$\\
A) $\frac{\sqrt{2}-\sqrt{6}}{4}$\\
B) $\sqrt{2}-\sqrt{6}$\\
C) $\sqrt{6}+\sqrt{2}$\\
D) $\frac{\sqrt{6}-\sqrt{2}}{4}$

Find an exact value.

cos(-7π)/(12)

A) (√(2)-√(6))/(4)

B) √(2)-√(6)

C) √(6)+√(2)

D) (√(6)-√(2))/(4)

Added by Miguel S.

Precalculus with Limits

Ron Larson 2nd Edition

Instant Answer

Solved by Expert Craig West

Step 1

To do this, we can use the unit circle. In the unit circle, the x-coordinate of a point on the circle represents the cosine of the angle formed by the radius and the positive x-axis. Since we are looking for cos 12, we need to find the x-coordinate of the Show more…

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