Answer:sin75=√(2+√3)/2
Step-by-step explanation:
Cosx=1-2sin^2(x/2) let x=150
Cos150=1-2sin^2(150/2) cos150=-√3/2
-(√3)/2=1-2sin^2(75)
2sin^2(75)=1+(√3)/2
2sin^2(75)=(2+√3)/2
Cross multiply
2x2sin^2(75)=2+√3
4sin^2(75)=2+√3
sin^2(75)=(2+√3)/4
Take square root of both sides
sin75=√(2+√3)/√4
sin75=√(2+√3)/2
