(A) ∫011+x3x2dx
Let u=1+x3
du=3x2dx
x2dx=31du
When x=0: u=1+03=1
When x=1: u=1+13=2
∫123u1du
=31[lnu]12
=31(ln2−ln1)
=31ln2
Therefore (A) → (IV)
(B) ∫0π3sinxdx
∫0π3sinxdx=3[−cosx]0π
=3[(−cosπ)−(−cos0)]
=3[(−(−1))−(−1)]
=3[1+1]
=6
Therefore (B) → (III)
(C) ∫−11sin5xcos6xdx
Check if the function is odd by replacing x with −x:
f(−x)=sin5(−x)cos6(−x)
=(−sinx)5(cosx)6
=−sin5xcos6x
=−f(x)
Since the function is odd and the interval [−1,1] is symmetric, the integral equals 0.
Therefore (C) → (I)
(D) ∫23x2−14dx
x2−14=(x−1)(x+1)4
Using partial fractions:
(x−1)(x+1)4=x−1A+x+1B
4=A(x+1)+B(x−1)
Put x=1: 4=2A so A=2
Put x=−1: 4=−2B so B=−2
∫23(x−12−x+12)dx
=2[ln∣x−1∣−ln∣x+1∣]23
=2[lnx+1x−1]23
=2[ln42−ln31]
=2[ln21−ln31]
=2ln23
=2loge23
Therefore (D) → (II)
The correct matching is:
(A) → (IV)
(B) → (III)
(C) → (I)
(D) → (II)