(a) Use the direction field of Problem 5 to estimate the values at x = 1 of the two solutions of the differential equation y' = y - x + 1 with initial values y(-1) = -1.2 and y(-1) = -0.8.

(b) Use a computer algebra system to estimate the values at x = 3 of the two solutions of this differential equation with initial values y(-3) = -3.01 and y(-3) = -2.99.

The lesson of this problem is that small changes in initial conditions can make big differences in results.