Evaluate the following expressions. your answer must be an angle −π/2≤θ≤π in radians, written as a multiple of π. note that π is already provided in the answer so you simply have to fill in the appropriate multiple. e. g. if the answer is π/2 you should enter 1/2. do not use decimal answers. write the answer as a fraction or integer. a. sin-1(sin((−5π/6)) =π.b. sin-1(sin(5π/3))=π.c. cos-1(cos(2π/3))=π.d. cos-1(cos(−7π/4))=π.