# Thread: Hoe to compute this

1. ## Hoe to compute this

Hi everyone,

I am studying discrete Fourier transform, i dont know how to input this into my calculator, im using Casio570ES.

$\displaystyle e^{-i2\pi}$, the answer is 1.
$\displaystyle e^{-i\frac{3\pi}{2}}$, im suppose to get i

can someone help me, thank you in advance for all your help & support,really appreciate.

2. Originally Posted by anderson
Hi everyone,

I am studying discrete Fourier transform, i dont know how to input this into my calculator, im using Casio570ES.

$\displaystyle e^{-i2\pi}$, the answer is 1.
$\displaystyle e^{-i\frac{3\pi}{2}}$, im suppose to get i

can someone help me, thank you in advance for all your help & support,really appreciate.
Not sure how to put this into the calculator directly, but you can use eulers formula to input it.

$\displaystyle e^{-i2\pi} = cos( 2 \pi ) - i sin( 2 \pi ) = 1 - 0 = 1$

$\displaystyle e^{-i\frac{3\pi}{2}} = cos( \frac{3\pi}{2} ) - i sin( \frac{3\pi}{2} ) = 0 -i(-1) = i$