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​If sin2A = 2 sinA, then A =?​
Question

If sin2A = 2 sinA, then A =?

A.

30°

B.

90°

C.

D.

60°

Correct option is C

Given:

sin2A=2sinA

Formula used:

The double-angle identity:

sin2A = 2sinAcosA

Solution:

Substitute the formula for sin⁡2A into the equation:

2sinAcosA = 2sinA

Divide both sides by 2sin⁡A (assuming sin⁡A0\neq0​):

cosA = 1 

cosA = cos00^\circ 

Since Cos A = 1 

A= 00^\circ 

The value of A is 00^\circ 

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