Let the area of the region enclosed by the curves y = 3x, 2y = 27 - 3x and y = 3x - x x be A. Then 10A is equal to
- 172
- 154
- 162
- 184
Answer
(3) 162
Solution
Meeting points: y = 3x & 2y = 27 - 3x (3, 9); line & curve (9, 0); y = 3x & curve (0, 0)
[figure]
A = 03 [3x - (3x - x3/2) ]dx + 39 [ 27 - 3x2 - 3x + x3/2 ]dx
= 25 35/2 + [ 27x2 - 9x24 + 25x5/2 ]39
= 18 35 + 81 - 162 + 4865 - 18 35
= 815
10A = 162
Answer: (3)