Is 1-cos(pi/n)=2sin^2(pi/(2n)) ?

The answer to whether 1-cos(pi/n)=2sin^2(pi/(2n)) is True

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prove 1-cos(pi/n)=2sin^2(pi/(2n))

prove

1 - cos (\frac{π}{n}) = 2 sin^{2} (\frac{π}{2 n})

True

Solution steps

1 - cos (\frac{π}{n}) = 2 sin^{2} (\frac{π}{2 n})

Manipulating right side

2 sin^{2} (\frac{π}{2 n})

Rewrite using trig identities

= - cos (\frac{π}{n}) + 1

= 1 - cos (\frac{π}{n})

We showed that the two sides could take the same form

\Rightarrow True

cos^{3} (x) = cos (x) - sin^{2} (x) cos (x)

cos (\frac{7 π}{12}) = cos (\frac{π}{3} + \frac{π}{4})

csc (θ) = 11

cos (2 x - 40) = 0.8

cos (\frac{π}{2} + x) = cos (x)

Is 1-cos(pi/n)=2sin^2(pi/(2n)) ?
The answer to whether 1-cos(pi/n)=2sin^2(pi/(2n)) is True