InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Let `f(x)=(ax + b )/(cx+d)`. Then the `fof (x)=x`, provided that : `(a!=0, b!= 0, c!=0,d!=0)`A. d=-aB. d=aC. a=b=c=d=1D. a=b=1 |
|
Answer» Correct Answer - D Given, `f(x)=(ax+b)/(cx+b)` `and fof(x)=x` `Rightarrow f((ax+b)/(cx+b))=x` `Rightarrow (a((ax+b)/(cx+b))+b)/(c((ax+b)/(cx+b))+d)=x` `Rightarrow (x(a^(2)+bc)+ab+bd)/(x(ac+cd)+bc+d^(2))=x` `Rightarrow d=-a` |
|