1. Let a, b E R, with a 0. Let f(x) = x for all x E [0, b] Show, from the definition, that (i) f is integrable on [0, b] and that (ii): 62 x dr = 2 Hint: Follow Example 14.15 in the lesson. 3. Let a, b E R, with a 0. Let f(x) = x2 for all x E [0, b] Show, from the definition, that (i) f is integrable on [0, b] and that (ii): 63 x' dr = 3