1. Integrate z2/(z4-1) counterclockwise around x2 + 16y2=4 2. Cauchy's Integral Forumula 3. Solution I found the points z=1,-1,i,-i where the function is not defined. Using partial fractions to split them up, and integral them separately. Only points z=1,-1 lies in the contour, so... [tex]\oint0.25/(z-1) + 0.25/(z+1) + 1/(z^2+1) dz[/tex] = 0.25(2Pi I + 2Pi I) + 0 = Pi I Ans is 0. can anyone find my mistake? 1. Integrate sinh2z/z4 counterclockwise around the unit circle. 2. Cauchy's Integral Forumula 3. Solution [tex]\oint sinh2z/z^4 = \oint sinh2z/(z-0)^4[/tex] = 2*PI*i/3! * (sinh2z)''' Differentiating sinh2z thrice gives 8cosh2z Hence, integral at z=0 = (8/3)*PI*i Ans is (8/3)*PI. Again, can anyone spot my mistake.