What is the value of i^20+1?

everyone on here is saying that it’s 2 ? but my options are:

a. 1
b. -1
c. -i
d. i

You know

Squaring both sides gives

Then raising both sides to any integer power gives

That is, any power of where the power is a multiple of 4 will always be equal to 1.

So

But perhaps you mean to write 20+1 as the exponent, in which case

1

step-by-step explanation:

it's the only multiple of both and the least