Rewrite the expression as the sine cosine or tangent of a do

Rewrite the expression as the sine, cosine, or tangent of a double-angle. Then find the calculator. Cos^2(-pi/6) - sin^2(-pi/6) Use the appropriate double-angle formula to rewrite the given expression as the sine,cose cos^2(-pi/6) - sin^2(-pi/6) = Square (Do not evaluate. Use integers or fractions for any numbers in the expression. Type your) Find the exact value of the trigonometric expression without the use of a calculator. cos^2(-pi/6) - sin^2(-pi/6) = Square (Use integral or fractions for any numbers in the expression. Type an exact answer, using)

Solution

given

cos^2(-/6) -sin^(-/6)

this of the form

cos^x -sin^2x = co2x (formula)

so here x=-/6

cos^2(-/6) -sin^(-/6) = cos(2.-/6)

=cos(-/3)

=cos(/3) (since cos(-x) =cosx)

=1/2 =(0.5)