Question

prove thst a=30° i) sin 3a = 4sina sin (60°-a) sin (60°+a)​

Answer 1

Answer:

Step-by-step explanation:

a=30°

i) sin 3a = 4sina sin (60°-a) sin (60°+a)​

sin 3(30°)=sin 90°=1=LHS

RHS=4sin30°×sin(60°-30°)×sin(60°+30°)

=(4×1/2)×(sin(30°))×(sin(90°)

=$2*\frac{1}{2}*1$

=1=LHS

∴LHS=RHS

Hence proved

 

Answer 2

Answer:

a=30°

LHS= sin 3a

=sin 3×30°

= sin 90°

= 1

RHS = 4sina sin (60°-a) sin(60+a)

= 4sin30°×sin(60°-30°) sin (60°+30°)

= 4×sin30°×sin30°×sin90°

= 4×1/2×1/2×1

= 1

RHS = LHS, hence proved.