Question 925788
How does (i+1)/(i-1) = -I
Multiply the NUM and DEN of the fraction by the conjugate of the DEN i+1
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(i+1)*(i+1)/((i-1)*(i+1)
= (i^2 + 2i + 1)/(i^2 - 1)
= (-1 + 2i + 1)/(-1 -1)
= 2i/(-2)
= -i