Solve 2cos(-2pi/12)= | Microsoft Math Solver

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2\cos(-\frac{1}{6}\pi )

Divide 2\pi by 12 to get \frac{1}{6}\pi .

2\cos(\frac{1}{6}\pi )

Use the property \cos(-x)=\cos(x).

2\times \frac{\sqrt{3}}{2}

Get the value of \cos(\frac{1}{6}\pi ) from trigonometric values table.

\sqrt{3}

Cancel out 2 and 2.

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