COMEDK2014MathematicsFunctions
If f(x)= 2 x-3 3 x+4 , then f⁻¹ ( -4 3 )=
Options
- AZero
- B3 4
- C- 2 3
- DNone of these
Correct answer
D. None of these
Step-by-step solution
f(x)= 2 x-3 3 x+4 Let f(x)=y= 2 x-3 3 x+4 On cross multiplication, we get aligned &3 x y+4 y=2 x-3 & x(3 y-2)=-3-4 y & x= -3-4 y 3 y-2 x=f⁻¹(y)= -3-4 y 3 y-2 aligned Put y=- 4 3 , we get aligned f⁻¹ (- 4 3 ) &= -3-4 (- 4 3 ) 3 (- 4 3 )-2 &= -3+ 16 3 -4-2 = 7 3 (-6) =- 7 18 aligned