Idon’t understand anything me with these 3

Recall the definition of a polynomial expression. find two polynomial expressions whose quotient, when simplified, is. use that division problem to determine whether polynomials are closed under division. then describe how theother three operations-addition, subtraction, and multiplication-are different from division of polynomials.

Me write an equation for the interior angles of this triangle that uses the triangle sum theorem

Which sum or difference identity would you use to verify that cos (180° - ∅) = -cos ∅? a. sin (α -β) = sin α cos β – cos α sin β b. cos (α -β) = cos α cos β – sin α sin β c. cos (α -β) = cos α cos β + sin α sin β d. sin (α + β) = sin α cos β + cos α sin β