AP EAMCET202125 Aug 2021Morning ShiftMathematicsIndefinite IntegrationActual
If 2 x+3 x(x+1)(x+2)(x+3)+1 d x= -1 a x^2+b x+c + , then value of a+b+c is equal to
Options
- A3
- B4
- C5
- D6
Correct answer
C. 5
Step-by-step solution
We have, aligned & 2 x+3 x(x+1)(x+2)(x+3)+1 d x= -1 a x^2+b x+c + & LHS = 2 x+3 x(x+3)(x+1)(x+2)+1 d x & = (2 x+3) d x (x^2+3 x ) (x^2+3 x+2 )+1 aligned Put x^2+3 x=t (2 x+3) d x=d t aligned & LHS = d t t^2+2 t+1 &= d t (t+1)^2 =- 1 t+1 + &= -1 x^2+3 x+1 + & a=1, b=3, c=1 & a+b+c=1+3+1=5 aligned