plz.. solve this question which are in the pic
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30.
2sin A-1=0
2sin A=1
sin A=1/2
A=30°
sin 3A=sin 90°=1
3sin A=3/2
4 sin^3 A=4/8
3sin A-4sin^3 A=3/2-1/2=1
sin 3A= 3sin A-4 sin^3A
b)
2 cos x=√3
cos x=√3/2
x=30°
sin 2x=sin 60°=√3/2
2sin X.cos x=2sin30° cos 30°=2*√3/2*1/2=√3/2
31.a)
2sin A-1=0
2sin A=1
sin A=1/2
A=30°
sin 3A=sin 90°=1
3sin A=3/2
4 sin^3 A=4/8
3sin A-4sin^3 A=3/2-1/2=1
sin 3A= 3sin A-4 sin^3A
b)
2 cos x=√3
cos x=√3/2
x=30°
sin 2x=sin 60°=√3/2
2sin X.cos x=2sin30° cos 30°=2*√3/2*1/2=√3/2
31.a)
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