Question

If A= 30 verify that
Sin 2a= 2tan A/1+tan sqareA

Answer 1

Solution:

It is given that,

A = 30°

LHS = sin2A

= sin (2×30)

= sin 60°

= √3/2 ---(1)

RHS = 2tanA/(1+tan²A)

= (2tan30°)/(1+tan² 30°)

= (2×1/√3)/[1+ (1/√3)²

= (2/√3)/[1+1/3]

= (2/√3)/(4/3)

= (2/√3)×(3/4)

= (2×√3×√3)/(√3×4)

After cancellation, we get

= √3/2 ---(2)

Therefore,

LHS = RHS

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