How can you use trigonometric functions to simplify 9 e^( ( 7 pi)/4 i ) 9e7π4i into a non-exponential complex number?

1 Answer
Jun 11, 2018

9 e^((7 pi)/4 i) =6.363961- 6.363961 i 9e7π4i=6.3639616.363961i

Explanation:

9 e^((7 pi)/4 i )9e7π4i

We know e^(i theta) = cos theta +i sin thetaeiθ=cosθ+isinθ

theta= (7 pi)/4 ~~ 5.497787θ=7π45.497787

:. 9 e^((7 pi)/4 i) = 9(cos ((7 pi)/4)+ i sin ((7 pi)/4)) or

9 e^((7 pi)/4 i) =6.363961- 6.363961 i [Ans]