prove cos(pi/3)= 1/2

Solution

prove

cos (\frac{π}{3}) = \frac{1}{2}

True

Solution steps

cos (\frac{π}{3}) = \frac{1}{2}

Manipulating left side

cos (\frac{π}{3})

Simplify

= \frac{1}{2}

We showed that the two sides could take the same form

\Rightarrow True

sec (- x) = sec (x)

cos (\frac{π}{3} + x) + cos (\frac{π}{3} - x) = cos (x)

sec^{2} (x) + tan^{2} (x) = 2 sec^{2} (x) - 1

cos^{2} (2 x) = \frac{1 + cos ( 4 x )}{2}

sin^{2} (θ) csc^{2} (θ) - sin^{2} (θ) = cos^{2} (θ)