AP EAMCET201726 Apr 2017Morning ShiftMathematicsIndefinite IntegrationActual
5 x^2+3 x^2 (x^2-2 ) d x=
Options
- A13 2 2 | 2 -x 2 +x |+ 3 2 x +C
- B13 4 2 | x+ 2 x- 2 |+ 3 2 x +C
- C13 4 2 | x- 2 x+ 2 |+ 3 2 x +C
- D5 3 2 | x+ 2 x- 2 |+ 3 5 x+C
Correct answer
C. 13 4 2 | x- 2 x+ 2 |+ 3 2 x +C
Step-by-step solution
Let, I= 5 x^2+3 x^2 (x^2-2 ) d x Put x^2=y . Then, aligned & 5 y+3=(y-2) A+y B & 5 y+3=y(A+B)-2 A aligned On comparing the coefficients, we get A+B=5 and 3=-2 AA= -3 2 and B= 13 2 Thus, 5 y+3 y(y-2) = 5 x^2+3 x^2 (x^2-2 ) =- 3 2 1 x^2 + 13 2 1 x^2-2 Now, I=- 3 2 d x x^2 + 13 2 d x x^2-2 gathered =- 3 2 (- 1 x )+ 13 2 1 2 2 | x- 2 x+ 2 |+C = 3 2 x + 13 4 2 | x- 2 x+ 2 |+C gathered