(7ctg( 3п/2 + a)) / 2sin( 3п - a), если a = 5п / 3

Question

(7ctg( 3п/2 + a)) / 2sin( 3п - a), если a = 5п / 3

Answer 1

-7tga/2sina=-7/2cosa=-7/2cos(5π/3)=-7/2cos(π/3)==-7/(2*1/2)=-7