Home
Class 12
MATHS
"If " (d)/(dx)f(x)=f'(x), " then " int(x...

`"If " (d)/(dx)f(x)=f'(x), " then " int(xf'(x)-2f(x))/(sqrt(x^(4)f(x)))dx ` is equal to

A

`(x^(2))/(f(x))+c`

B

`|x|f'(x)+c`

C

`(2sqrt(f(x)))/(|x|)+c`

D

`|x|sqrt(f(x))+c`

Text Solution

Verified by Experts

The correct Answer is:
C

`I=int(xf'(x)-2f(x))/(x^(2)sqrt(f(x)))dx `
`=int((x^(2)f'(x)-2xf(x))/(x^(4)))/(sqrt((f(x))/(x^(2))))dx`
`"Put " (f(x))/(x^(2))=t^(2) `
` :. (x^(2)f'(x)-2xf(x))/(x^(4))dx=2t dt `
` :. I=int(2t dt)/(t)=2t+c=(2sqrt(f(x)))/(|x|)+c`
Promotional Banner

Topper's Solved these Questions

  • INDEFINITE INTEGRATION

    CENGAGE|Exercise Exercise (Multiple)|17 Videos
  • INDEFINITE INTEGRATION

    CENGAGE|Exercise Exercise (Comprehension)|17 Videos
  • INDEFINITE INTEGRATION

    CENGAGE|Exercise Exercise 7.9|15 Videos
  • HYPERBOLA

    CENGAGE|Exercise JEE Advanced Previous Year|14 Videos
  • INEQUALITIES AND MODULUS

    CENGAGE|Exercise Single correct Answer|21 Videos

Similar Questions

Explore conceptually related problems

If (d)/(dx)f(x)=4x^(3)-(3)/(x^(4)) , then f(x) is

If f(a+b-x)=f(x) , then int_(a)^(b)xf(x)dx is equal to

Ifxf(x)=3f^2(x)+2,t h e nint(2x^2-12 xf(x)+f(x))/((6f(x)-x)(x^2-f(x))^2)dx equal. 1/(x^2-f(x))+c (b) 1/(x^2+f(x))+c 1/(x-f(x))+c (d) 1/(x+f(x))+c

Consider two differentiable functions f(x),g(x) satisfying 6intf(x)g(x)dx=x^(6)+3x^(4)+3x^(2)+c and 2 int(g(x)dx)/(f(x))=x^(2)+c, " where " f(x) gt 0 AA x in R. int (g(x)-f(x))dx is equal to

If f(x)=f(a+x) then show that int_(0)^(2a)f(x)dx=2int_(0)^(a)f(x)dx .

Evaluate int_(0)^(a)(f(x))/(f(x)+f(a-x)) dx.

If f'(a)=2 and f(a)=4 then lim_(xtoa)(xf(a)-af(x))/(x-a) equals to

CENGAGE-INDEFINITE INTEGRATION-Exercise (Single)
  1. intx((lna^(x/2)/(3a^((5x)/2)b^(3x))+(lnb^b^x)/(2a^(2x)b^(4x)))dx(w h e...

    Text Solution

    |

  2. int(3+2cosx)/((2+3cosx)^2)dxi se q u a lto ((sinx)/(3cosx+2))+c (b) ...

    Text Solution

    |

  3. "If " (d)/(dx)f(x)=f'(x), " then " int(xf'(x)-2f(x))/(sqrt(x^(4)f(x)))...

    Text Solution

    |

  4. The value of the integral int((1-costheta)^(2/7))/((1+costheta)^(9/7))...

    Text Solution

    |

  5. If int(dx)/(sqrt(sin^(3)xcos^(5)x))=a sqrt(cot x)+bsqrt(tan^(3)x)+c, t...

    Text Solution

    |

  6. "I f"int(dx)/(cos^3xsqrt(sin2x))=a(tan^2x+b)sqrt(tanx)+c

    Text Solution

    |

  7. If int(dx)/((x+2)(x^(2)+1)) = alog|1+x^(2)|+btan^(-1)x+ 1/5log|x+2|+C,...

    Text Solution

    |

  8. Ifint(3e^x-5e^(-1))/(4e^x+5e^(-x))dx=a x+bln(4e^x+5e^(-x))+C ,t h e n

    Text Solution

    |

  9. If int f(x) sinx cosx dx=(1)/(2(b^(2)-a^(2))) "In " f(x)+c," then " f...

    Text Solution

    |

  10. int(x^9)/((4x^2+1)^6) dx is equal to

    Text Solution

    |

  11. If int1/(xsqrt(1-x^3))dx=alog|(sqrt(1-x^3)-1)/(sqrt(1-x^3)+1)|+b ,t h...

    Text Solution

    |

  12. The value of the integral int(x^2+x)(x^(-8)+2x^(-9))^(1/(10))dx is 5/(...

    Text Solution

    |

  13. int(x^3dx)/(sqrt(1+x^2))i se q u a lto 1/3sqrt(1+x^2)(2+x^2)+C 1/3...

    Text Solution

    |

  14. If I=int (dx)/((a^(2)-b^(2)x^(2))^(3//2)), then I equals

    Text Solution

    |

  15. int(x^4-1)/(x^2sqrt(x^4+x^2+1))dx= sqrt(x^2+1/(x^2)+1)+C (sqrt(x^4...

    Text Solution

    |

  16. int(sqrt(x^2+1))/(x^4)dx=

    Text Solution

    |

  17. int (1+2x^(6))/((1-x^(6))^(3//2))dx is equal to

    Text Solution

    |

  18. The integral int(2x^(12)+5x^(9))/((x^(5)+x^(3)+1)^(3)) dx is equal to

    Text Solution

    |

  19. If In=int( lnx)^n dx then In+nI(n-1)

    Text Solution

    |

  20. Let inte^x{f(x)-f^(prime)(x)}dx=varphi(x)dot Then inte^xf(x)dx is varp...

    Text Solution

    |