JEE 2022 — Mathematics PYQ
JEE | Mathematics | 2022If ∫01(2x−2x−x2)dx=∫01(1−1−y2−2y2)dy+∫12(2−2y2)dy+I, then I equals:
Choose the correct answer:
- A.
∫01(1+1−y2)dy
∫01(1−1−y2)dy
Explanation
L.H.S.:
L.H.S.=∫022xdx−∫022x−x2dx
=2[32x3/2]02−∫021−(x−1)2dx
=38−2∫011−y2dy
R.H.S.:
R.H.S.=∫01(1−2y2)dy−∫011−y2dy+∫12(2−2y2)dy+I
=[y−6y3]01−∫011−y2dy+[2y−6y3]12+I
=65−∫011−y2dy+65+I=35−∫011−y2dy+I
Equating L.H.S and R.H.S:
38−2∫011−y2dy=35−∫011−y2dy+I
I=1−∫011−y2dy
I=∫01(1−1−y2)dy
Correct Option: (C)
Explanation
L.H.S.:
L.H.S.=∫022xdx−∫022x−x2dx
=2[32x3/2]02−∫021−(x−1)2dx
=38−2∫011−y2dy
R.H.S.:
R.H.S.=∫01(1−2y2)dy−∫011−y2dy+∫12(2−2y2)dy+I
=[y−6y3]01−∫011−y2dy+[2y−6y3]12+I
=65−∫011−y2dy+65+I=35−∫011−y2dy+I
Equating L.H.S and R.H.S:
38−2∫011−y2dy=35−∫011−y2dy+I
I=1−∫011−y2dy
I=∫01(1−1−y2)dy
Correct Option: (C)

