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प्रश्न
Sin 2A = 2 sin A is true when A =
विकल्प
0°
30°
45°
60°
उत्तर
We are given sin 2A=` 2sin A. cos.A`
So
⇒` 2 sin A. cos A=2 sin A`
⇒` 2 sin A. cos A= 2 sin A`
⇒ `cos A=1`
⇒ `cos A= cos 0°`
`As A= 0°`
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