Use the Pythagorean Identity to write the double angle formula for cosine in two alternate forms by filling in the blanks using a trig identity or simplifying your answer at each step.

(a) $\cos(2t) = 1 - 2 \sin^2(t) = 1 - \Big($ $\Big) =$ help (formulas)

(b) $\cos(2t) = 2\cos^2(t) - 1 = 2\cos^2(t) - \Big($ $\Big) =$ help (formulas)

Hint: