Question

If 2cos,3 A=1find the value of A

Answer 1

Question :-- if 2 cos3A = 1, Find the value of A ?

Formula used :-

• Cos60° = 1/2

Solution :--

→ 2cos3A = 1

Taking 2 in RHS side , it will be in Divide now,

→ cos3A = 1/2

Now, putting value of cos60° = 1/2 in RHS , we get,

→ Cos3A = cos60°

Comparing we get,

→ 3A = 60°

Dividing both sides by 3 now, we get,

→ A = 20° (Ans).

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Answer 2

Answer:

Value of A is 20°

Explanation:

Correct Question :-

If 2cos3 A=1 , find the value of A

We Have :-

2cos3A=1

To Find :-

Value of A

Solution :-

cos 60° = 1 / 2

Acc to Ques

2 cos 3A = 1

cos 3A = 1 / 2

cos 3A = cos 60°

3A = 60°

A = 60 / 3

A = 20°

Value of A is 20°