Question

Question #a5768

Answer 1

Good question...

Explanation:

`color(red)(costheta+iotasintheta` is a complex number,in which `color(red)(costheta` lies on real axis and `color(red)(iotasintheta`
lies on the imaginary axis of the argand plane.

But `color(green)(costheta+sintheta` is a just a simple number.

Hope it helps...
Thank you...