Question

if f(x)=x²-2x+3 for all x€R . Find f(f(x))​

Answer 1

f(x)=x²-2x+3 for all x€R

then,

f(fx))=(x²-2x+3)²-2(x²-2x+3)+3

= (x²-2x+3)(x²-2x+3-2) + 3

= (x²-2x+3)(x²-2x+1) + 3

= x⁴-2x³+x²-2x³+4x²-2x+3x²-6x+3 + 3

= x⁴-4x³+8x²-8x+6