Let the area enclosed between the curves |y|=1-x2 and x2+y2=1 be . If 9 = + ; , are integers, then the value of | - | equals:
- 15
- 18
- 33
- 27
Answer
(3) 33
Solution
[figure]
The parabolas |y|=1-x2 lie inside the circle; the 4 shaded crescents are equal
=4 [ 4- 01(1-x2)dx ]=4 [ 4- 23 ]= - 83
⇒ 9 =9 -24 ⇒ =9, =-24
∴ | - |=33
Answer: (3)