Question 5440
 Be careful about your notation. It seems that you should type as
 i^(-17)

 Using exponential law,
 
 i^(-17) = (i^17)^(-1) = (i^16 * i)^(-1) [since i^16= (i^4)^4 & i^4 = 1 ]
  = i^(-1) = 1/i = -i. [since i^2 = -1]

 Kenny