Manipal MET2022MathematicsIndefinite Integration
If f(x) d x=g(x) , then x^9 f (x^5 ) d x is equal to
Options
- A1 5 (x^5 g (x^9 )-4 g(x) d x+C .
- B1 5 [x^9 g (x^5 )- 1 5 x^4 g (x^5 ) d x+C .
- C1 5 [g (x^9 )+ g (x^5 ) d x ]
- Dx^5 5 g (x^5 )- x^4 g (x^5 ) d x+C
Correct answer
D. x^5 5 g (x^5 )- x^4 g (x^5 ) d x+C
Step-by-step solution
Given that, f(x) d x=g(x) Let I= x^9 (x^5 ) d x Put x^5=t 5 x^4 d x=d t aligned & = 1 5 t f(t) d t & = 1 5 [t f(t) d t- [f(t) d t] . aligned [integrating by part] aligned & = 1 5 [t g(t)- g(t) d t ] & = 1 5 [x^2 g (x^5 )-5 g (x^5 ) x^4 d x ]+C & = x^5 5 g (x^5 )- x^4 g (x^5 ) d x+C aligned