The problem is : Use conditions to give a function pow[x,r]. Be sure to use the string "imaginary", and to test your result on pow[0,0], pow[2,0], pow[2,2], pow[-1,1/3], pow[-1,1/2], and pow[-1, [Pi]]. I'm unsure how to set it up to correctly for example, when I try pow[x, r] := "undefined" /; x = 0 && r = 0, it gives me 0 instead of undefined as the output