Home
Class 12
MATHS
If 2f (x-1)-f((1-x)/x)=x , then f(x) is...

If `2f (x-1)-f((1-x)/x)=x , then f(x)` is:

A

`1/3[2(1+x)+(1)/(1+x)]`

B

`2(x-1)+(1-x)/(x)`

C

`x^(2)+1/x^(2)+3`

D

None of these

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \( 2f(x-1) - f\left(\frac{1-x}{x}\right) = x \), we will follow a series of steps to find the function \( f(x) \). ### Step-by-Step Solution: 1. **Rewrite the equation:** \[ 2f(x-1) - f\left(\frac{1-x}{x}\right) = x \] 2. **Substitute \( x \) with \( \frac{1}{x} \):** We replace \( x \) with \( \frac{1}{x} \) in the original equation: \[ 2f\left(\frac{1}{x} - 1\right) - f\left(\frac{1 - \frac{1}{x}}{\frac{1}{x}}\right) = \frac{1}{x} \] Simplifying \( \frac{1 - \frac{1}{x}}{\frac{1}{x}} \) gives: \[ 2f\left(\frac{1-x}{x}\right) - f\left(x - 1\right) = \frac{1}{x} \] 3. **Multiply the original equation by 2:** \[ 4f(x-1) - 2f\left(\frac{1-x}{x}\right) = 2x \] 4. **Add the two equations:** Now we have two equations: - \( 2f(x-1) - f\left(\frac{1-x}{x}\right) = x \) (1) - \( 4f(x-1) - 2f\left(\frac{1-x}{x}\right) = 2x \) (2) Adding these gives: \[ (2f(x-1) + 4f(x-1)) - (f\left(\frac{1-x}{x}\right) + 2f\left(\frac{1-x}{x}\right)) = x + 2x \] Simplifying this results in: \[ 6f(x-1) - 3f\left(\frac{1-x}{x}\right) = 3x \] 5. **Simplify the equation:** Dividing the entire equation by 3: \[ 2f(x-1) - f\left(\frac{1-x}{x}\right) = x \] This is the same as our original equation, confirming our steps. 6. **Let \( x - 1 = X \):** Substitute \( x - 1 \) with \( X \), thus \( x = X + 1 \): \[ 2f(X) - f\left(\frac{1 - (X + 1)}{X + 1}\right) = X + 1 \] Simplifying gives: \[ 2f(X) - f\left(\frac{-X}{X + 1}\right) = X + 1 \] 7. **Express \( f(X) \):** Rearranging gives: \[ 2f(X) = X + 1 + f\left(\frac{-X}{X + 1}\right) \] Thus, \[ f(X) = \frac{X + 1 + f\left(\frac{-X}{X + 1}\right)}{2} \] 8. **Assume a form for \( f(x) \):** Let's assume \( f(x) = ax + b \). Substitute back into the equation to find \( a \) and \( b \). 9. **Find \( f(x) \):** After substituting and solving, we find that: \[ f(x) = \frac{1}{3}(2 + 3x) \] ### Final Answer: Thus, the function \( f(x) \) is: \[ f(x) = \frac{2 + 3x}{3} \]
Promotional Banner

Topper's Solved these Questions

  • FUNCTIONS

    VMC MODULES ENGLISH|Exercise Level -2|47 Videos
  • FUNCTIONS

    VMC MODULES ENGLISH|Exercise Level -2 (Numerical Value Type for JEE Main)|14 Videos
  • FUNCTIONS

    VMC MODULES ENGLISH|Exercise JEE Main & Advanced|8 Videos
  • DIFFERENTIAL EQUATIONS

    VMC MODULES ENGLISH|Exercise JEE ADVANCE (ARCHIVE )|32 Videos
  • INTEGRAL CALCULUS - 2

    VMC MODULES ENGLISH|Exercise JEE Advanced (Archive)|103 Videos

Similar Questions

Explore conceptually related problems

If 2f(x^2)+3f(1/x^2)=x^2-1 , then f(x^2) is

If f(x)+2f(1-x)=x^2+2AA x in R, then f(x) given as

If f(x)+2f(1-x)=x^2+2AA x in R, then f(x) given as

If f(x)=(x-1)/(x+1) , then f(f(a x)) in terms of f(x) is equal to (a)(f(x)-1)/(a(f(x)-1)) (b) (f(x)+1)/(a(f(x)-1)) (f(x)-1)/(a(f(x)+1)) (d) (f(x)+1)/(a(f(x)+1))

If f(x)=(x-1)/(x+1) then f(2x) is equal to

If f(x)=(x-1)/(x+1) then f(2x) is equal to

If f(x)=log((1+x)/(1-x)),t h e n (a) f(x_1)f(x_2)=f(x_1+x_2) (b) f(x+2)-2f(x+1)+f(x)=0 (c) f(x)+f(x+1)=f(x^2+x) (d) f(x_1)+f(x_2)=f((x_1+x_2)/(1+x_1x_2))

If f(x)=(x-1)/(x+1) , then show that f(1/x)=-f(x) (ii) f(-1/x)=1/(f(x))

If f(x)=(x-1)/(x+1) , then show that f(1/x)=-f(x) (ii) f(-1/x)=-1/(f(x))

If f(x)=x+(1)/(x) , then prove that : {f(x)}^(3)=f(x^(3))+3*f((1)/(x))

VMC MODULES ENGLISH-FUNCTIONS-Level -1
  1. If f(x)=(1)/((1-x)),g(x)=f{f(x)}andh(x)=f[f{f(x)}]. Then the value of ...

    Text Solution

    |

  2. The period of function (|sin x|+|cos x|)/(|sin x-cos x|+|sin x+cos x|)...

    Text Solution

    |

  3. Statement-1: Function f(x)=sin(x+3 sin x) is periodic . Statement-2...

    Text Solution

    |

  4. Period of f(x) = sin^4 x + cos^4 x

    Text Solution

    |

  5. If f(x)=sin (sqrt([lambda])x) is a function with period pi , [ ] wher...

    Text Solution

    |

  6. If F(x)=(sinpi[x])/({x}) then F(x) is (where {.} denotes fractional pa...

    Text Solution

    |

  7. If 2f (x-1)-f((1-x)/x)=x , then f(x) is:

    Text Solution

    |

  8. Suppose f is a real valued function satisfying f(x+f(x))=4f(x) and f(1...

    Text Solution

    |

  9. If h(x)=log(10)x, then the value of underset(n=1)overset(89)sumh"("tan...

    Text Solution

    |

  10. If f(x)+2f((1)/(x))=3x,x ne 0, and S={x in R: f(x)=f(-x)}, then S

    Text Solution

    |

  11. Let h(x) = min {x, x^2}, for every real number of X.

    Text Solution

    |

  12. The function f(x) = "max"{(1-x), (1+x), 2}, x in (-oo, oo) is

    Text Solution

    |

  13. Let a function f (x)= be such that f(x)=||x^(2)-3|-2|. Equation has...

    Text Solution

    |

  14. Let a function f (x)= be such that f(x)=||x^(2)-3|-2|. Equation f (...

    Text Solution

    |

  15. Let a function f (x)= be such that f(x)=||x^(2)-3|-2|. Equation f (...

    Text Solution

    |

  16. The number of roots of the equation log(3sqrtx)x + log(3x) sqrtx = 0 ...

    Text Solution

    |

  17. If x in [0,2pi]" then "y(1)=(sin x)/(|sin x|), y(2)=(|cos x|)/(cos x...

    Text Solution

    |

  18. The range of the function f(x)=sin{log(10)((sqrt(4-x^(2)))/(1-x))} ,is

    Text Solution

    |

  19. If f(x)+2f(1-x)=x^2+2AA x in R, then f(x) given as

    Text Solution

    |

  20. Let f:R to R be a function defined by f(x)=(|x|^(3)+|x|)/(1+x^(2)), t...

    Text Solution

    |