a. The current, i, through a pn-junction diode is given by i = Is e(11600+T)V4) _ 1]. where V is the voltage, Is , 1 and A are constants. If the a.c. resistance (r) of the diode is defined 1 as r= , find r. di/dv (6 Marks) b. Assuming y is a function of x, find dx for Tx sec(y) - 3y sin(xy) = exy (13 Marks) c. Using the L'Hopital's Rule, evaluate the following limit: (6 Marks) Tx2-5 1-e-Tx lim + lim X+00 e 2Tx X-0 e3x