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Popular >

2cos^2(165)-1

Solution

2 cos^{2} (16 5^{\circ}) - 1

Solution

\frac{2 + 3}{2} - 1

+1

Solution steps

2 cos^{2} (16 5^{\circ}) - 1

Rewrite using trig identities:

cos (16 5^{\circ}) = \frac{- 6 - 2}{4}

= 2 (\frac{- 6 - 2}{4})^{2} - 1

Simplify

2 (\frac{- 6 - 2}{4})^{2} - 1 : \frac{2 + 3}{2} - 1

= \frac{2 + 3}{2} - 1

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Frequently Asked Questions (FAQ)

What is the value of 2cos^2(165)-1 ?
The value of 2cos^2(165)-1 is (2+sqrt(3))/2-1