Show your work for any calculations needed or simplifications made! Clearly show your work and the steps necessary to prove an identity or to solve an equation. "Exact" solutions mean rational expressions - not decimals the calculator returns! 1. Find the exact value of Cos + - by using trigonometric identities to rewrite and simplify. 2. Verify the identity sin(A - B) sin(A + B) = sin A - sin? B.3. Use trigonometric identities and algebra to find exact solutions tan(X + ) - cos X+ - = 0. Give all solutions on the interval [0,2t] 4. Given that sin A = _ cos B = -- and that both A and B are in quadrant II, find cos(A - B). Simplify it to a single value, leaving it in the form of a rational number