Question

if A =30 verify that cos2A =1-tan square A/1+tan square A

Answer 1

Hope it helps uh dear friend ✌️✌️✌️

Answer 2

Hey user !!

Here is your answer !!
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♦♦ Given -> A=30°

♦♦ Proof ->Cos2A=1-Tan^2A/1+Tan^2A

LHS -
Cos2A=Cos60°=1/2

RHS -
(TanA=1/√3)

1-(1/√3)^2 / 1 + (1/√3)^2

1-1/3/1+1/3

By taking LCM

(2/3)/(4/3)

1/2

Hence LHS =RHS

Proved!!

Hope it is satisfactory :-)
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