Home
Class 12
MATHS
If fa n dg are two distinct linear funct...

If `fa n dg` are two distinct linear functions defined on `R` such that they map `{-1,1]` onto `[0,2]` and `h : R-{-1,0,1}vecR` defined by `h(x)=(f(x))/(g(x)),` then show that `|h(h(x))+h(h(1/x))|> 2.`

Text Solution

Verified by Experts

Let two linear functions be
`f(x)=ax +b" and " g(x) =cx +d.`
They map `[-1,1] to [0,2]` and mapping is onto.
Therefore, `f(-1)=0 and f(1)=2`
`and g(-1)=2 and g(1)=0,` i.e.,
`-a+b=0 and a+b=2 " (1) " `
`and -c+d=2 and c+d=0 " (2) " `
`or a=b=1 and c= -1, d=1`
`or f(x)=x+1 and g(x)=-x+1`
`or h(x)=(x+1)/(1-x) or h(h(x)) =((x+1)/(1-x)+1)/((x+1)/(1-x)-1)=(1)/(x)`
` or h(h(1//x))=x`
`or |h(h(x))+h(h(1//x))|=|x+1//x| gt 2`
Promotional Banner

Topper's Solved these Questions

  • RELATIONS AND FUNCTIONS

    CENGAGE|Exercise Exercise 1.1|15 Videos
  • RELATIONS AND FUNCTIONS

    CENGAGE|Exercise Exercise 1.2|5 Videos
  • Quadratic Equations, Inequalities, Modulus and Logarithms

    CENGAGE|Exercise Question Bank|31 Videos
  • SCALER TRIPLE PRODUCTS

    CENGAGE|Exercise DPP 2.3|11 Videos

Similar Questions

Explore conceptually related problems

If f and g are two distinct linear functions defined on R such that they map {-1,1] onto [0,2] and h:R-{-1,0,1}rarr R defined by h(x)=(f(x))/(g(x)) ,then show that |h(h(x))+h(h((1)/(x)))|>2

If f,g,\ h are three functions defined from R\ to\ R as follows: the range of h(x)=x^2+1

Let f(x) be a function defined on [-2,2] such that f(x)=-1-2<=x<=0 and f(x)=x-1,0

If f,g,\ h are three functions defined from R\ to\ R as follows: Find the range of f(x)=x^2

If f(x)=(1)/(x), evaluate lim_(h rarr0)(f(x+h)-f(x))/(h)

Let A=R-{2} and B=R-{1}. If f:A rarr B is a mapping defined by f(x)=(x-1)/(x-2), show that f is bijective.

Let A=R-[2] and B=R-[1]. If f:A rarr B is a mapping defined by f(x)=(x-1)/(x-2), show that f is bijective.

If f(x)=(sin(pi x)/(4))/(x+1) , then lim_(h rarr0)(f(1+h)-f(1))/(h^(2)+2h) is

A function is said to be bijective if it is both one-one and onto, Consider the mapping f : A rarr B be defined by f(x) = (x-1)/(x-2) such that f is a bijection. Let g : R - {2} rarr R - {1} be defined by g(x) = 2f(x) - 1 . Then g(x) in terms of x is :

CENGAGE-RELATIONS AND FUNCTIONS-Solved Examples And Exercises
  1. If fa n dg are two distinct linear functions defined on R such that th...

    Text Solution

    |

  2. Find the inverse of the function: f:(-oo,1] rarr [1/2,oo],w h e r ef(...

    Text Solution

    |

  3. Find the value of x for which function are identical. f(x)=xa n dg(x)=...

    Text Solution

    |

  4. Find the value of x for which function are identical. f(x)=cosxa n dg(...

    Text Solution

    |

  5. Find the value of x for which function are identical. f(x)=(sqrt(9-x^2...

    Text Solution

    |

  6. Find the inverse of the function: f: R rarr (-oo,1)gi v e nb yf(x)=1-...

    Text Solution

    |

  7. f:(2,3)vec(0,1)d efin e db yf(x)=x-[x],w h e r e[dot] represents the g...

    Text Solution

    |

  8. Find the inverse of the function: f(x)={x^3-1, ,x<2x^2+3,xgeq2

    Text Solution

    |

  9. Find the inverse of the function: f:[-1,1]rarr[-1,1]defined byf(x)=x|...

    Text Solution

    |

  10. If f(x+y+1)={sqrt(f(x))+sqrt(f(y))}^2 and f(0)=1AAx ,y in R ,d e t e ...

    Text Solution

    |

  11. Let f(x)=(9^x)/(9^x+3) . Show f(x)+f(1-x)=1 and, hence, evaluate. f(1/...

    Text Solution

    |

  12. If f(x+2a)=f(x-2a),t h e np rov et h a tf(x)i sp e r iod i cdot

    Text Solution

    |

  13. Let g(x) be a function such that g(a+b)=g(a)dotg(b)AAa , b in Rdot If...

    Text Solution

    |

  14. Find the value of x for which function are identical. f(x)=tan^(-1)x+t...

    Text Solution

    |

  15. The period of f(x)=[x]+[2x]+[3x]+[4x]+[n x]-(n(n+1))/2x , where n in ...

    Text Solution

    |

  16. Plot y=|x|,y=|x-2|, and y=|x+2|

    Text Solution

    |

  17. If f(x+1/2)+f(x-1/2)=f(x)fora l lx in R , then the period of f(x) is ...

    Text Solution

    |

  18. If for all real values of ua n dv ,2f(u)cosv=(u+v)+f(u-v), prove that ...

    Text Solution

    |

  19. If the period of (cos(sin(n x)))/(tan(x/n)),n in N ,i s6pi , then n= ...

    Text Solution

    |

  20. If f: X rarr[1,oo) is a function defined as f(x)=1+3x^3, find the su...

    Text Solution

    |

  21. Find the period (if periodic) of the following function ([.] denotes ...

    Text Solution

    |