Q24 of 29 Page 5

If a = cos θ + i sin θ, find the value of .

Given:


a = cos θ + i sin θ


⇒


We know that,


1 + cos2θ = 2cos2θ,


1 - cos2θ = 2sin2θ


sin2θ = 2sinθcosθ


⇒


⇒


⇒


⇒


We know that i2 = - 1


⇒


⇒


⇒


∴ The value of is .


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