Question

Докажите равенство: sin75⁰ cos75⁰ = 1/4 

Answer 1

 sin75⁰ cos75⁰=(1/2)*sin(2*75)=(1/2)*sin(150)=(1/2)*sin(180-150)=(1/2)*sin(30)=

=(1/2)*(1/2)=1/4