Diketahui f(x) = 1 - 2x dan (g°f)(x) = 4x2 - 6x + 3 tentukan a.rumus fungsi g x) b.nilai (f°g)(4)

a. gof =4x2-6x+3
g (1-2x) = 4x2-6x+3
g = 4 (1-2x)^2 -6(1-2x)+3
    = 4 (1-4x+4x^2)-6+12x+3
     = 4-16x+16x^2-6+12x+3
      = 16x^2-4x+1


b. (fog)(x) = f (16x^2-4x+1
=16 (1-2x)^2 - 4 (1-2x)+1
=16 (1-4x+4x^2) -4+8x+1
=16-64x+64x^2-4+8x+1
=64x^2-56x+13

masukkan 4

= 64 (4)^2-56(4)+13 = 813