Question

Помогите пожалуйста!!!!!!!))))

Answer 1

42√6 cos(π/4) cos(5π/6)=42√6 ·(√2/2) cos(π-π/6)=
=42√6 ·(√2/2)·(-√3/2)=-42·6/4=-63

Answer 2

не верно

Answer 3

-63

Answer 4

ДА....-63