Find the exact real number value in radian measure of each o

Find the exact real number value in radian measure of each of the following a) cos^-1(-Squareroot 2/2) = ________ b) sin^-1(sin -2 pi/3) = ________

Solution

cos ^-1(-sqrt2/2)

cos^-1(cos 3pi/4)

cos^-1cos theta = theta

3pi/4

b. sin^-1sin(-2pi/3) = -pi/3