KCET2012MathematicsDefinite Integration
_ / 6 ^ / 3 ³ x ³ x+ ³ x d x is equal to
Options
- A2
- B3
- C12
- D6
Correct answer
D. 6
Step-by-step solution
Let I= _ / 6 ^ / 3 ³ x ³ x+ ³ x d x aligned &= _ / 6 ^ / 3 ³ ( 3 + 6 -x ) ³ ( 3 + 6 -x )+ ³ ( 3 + 6 -x ) d x &= _ / 6 ^ / 3 ³ ( 2 -x ) ³ ( 2 -x )+ ³ ( 2 -x ) d x &I= _ / 6 ^ / 3 ³ x ³ x+ ³ x d x aligned On adding Eqs. (i) and (ii), we get aligned 2 I &= _ / 6 ^ / 3 ³ x+ ³ x ³ x+ ³ x d x &=[x]_ / 6 ^ / 3 &= 3 - 6 = 2 - 6 = 6 aligned