MHT CET20239 May 2023Morning ShiftMathematicsFunctionsActual
f : R - (- 3 5 ) R is defined by f(x)= 3 x-2 5 x+3 , then f f(1) is
Options
- A1
- B-13 29
- C13 29
- D-1
Correct answer
B. -13 29
Step-by-step solution
aligned & f(x)= 3 x-2 5 x+3 & aligned f(f(x)) & = 3 ( 3 x-2 5 x+3 )-2 5 ( 3 x-2 5 x+3 )+3 & = 3(3 x-2)-2(5 x+3) 5(3 x-2)+3(5 x+3) & = 9 x-6-10 x-6 15 x-10+15 x+9 & = -x-12 30 x-1 aligned & fof (1)= -1-12 30-1 = -13 29 aligned