Q3. Matlab exercise: apg Let we have the Heat equation u =u,, -11, x >0 u(0, y)=cos y, -15ysi u(x,-1) = u(x,1)=e*cosl x>0 a)Solve with Explicit method from x=0 to x=0.5 with h=0.1 and k=0.005> b) graph the Approximation solution and exact solution u(x, y)= e *cos y Worksheet 4 Q1: Let we have the Heat equation u = Uyy O0, and 2 ocych u(0, y)= 21- y) {