1. Evaluate each integral by making an appropriate substitution. (a) j x dx 12+4 (b) 'a'3 '6 x D eI +1?" (-3) Itanxseelxdx 2. Find the area of the region bounded above by the graph of 30:) = l and below by the graph off(x) = x2 +2x2. 3. Let R be the closed region between the graphs of y t 2.5 and y = 2.1: on the interval [0, 1]. Find the volume V of the solid obtained by revolving R about the 1-: axis. ______________________ L _______ _________________________________