Question

please solve this answer
its urgent guys!

Answer 1

its just substituting,

sin2(30)=2sin(30)cos(30)

sin60=(2×1×√3)/(2×2)

√3/2=√3/2

cos3(30)=4cos^3(30)-3cos(30)

cos90=4(√3/2)^3-3(√3/2)

0=4(3√3/8)-3√3/2

0=3√3/2-3√3/2

0=0

Answer 2

hope it helps you........