Consider the IVPs: 
        (A)  y'+2y = 1,   0<t<1 ,  y(0)=2.
        (B)  y' = y(1-y), 0<t<1 ,  y(0)=1/2.
1. For each one, do the following:
  a. Find the exact solution y(t) and evaluate it at t=1.
  b. Apply Euler's method with  Δt=1/4  to find Y4 ≈ y(1).
     Make a table of tn, Yn for n=0,1,2,3,4.
  c. Find the error at t=1.
2. Euler's method is obtained by approximating y'(tn) by a forward finite difference.
   Use the backward difference approximation to y'(tn+1)...