3. of cep/ 9 rot R O 3 92Figure 3 (a) By writing sec 0 as show that when x = 3 sec 0, cos O dx = 3 sec 0 tan 0 de (2) Figure 3 shows a sketch of part of the curve C with equation * - 9 x>3 X The finite region R, shown shaded in Figure 3, is bounded by the curve C, the x-axis and the line with equation x = 6 (b) Use the substitution x = 3 sec 0 to find the exact value of the area of R. [Solutions based entirely on graphical or numerical methods are not acceptable. ]