ONLY DO 4 Please Let CR denote the upper half of the circle

Let C_R denote the upper half of the circle |z| = R (R > 2), taken in the counterclockwise direction. Show that |integral_C_R 2z^2 - 1/z^2=4 + 5z^2 + 4 dz| lessthanorequalto pi R(2R^2 + 1)/(R^2 - 1)(R^2 - 4). Then, by dividing the numerator and denominator on the right here by R^4, show that the value of the integral tends to zero as R tends to infinity. (Compare with Example 2 in Sec. 47.) Let C_R be the circle |z| = R (R > 1), described in the counterclockwise direction. Show that

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