Bantuin dong☺

Diketahui f(x)= 3x+1 dan g(x)=x²-2

Tentukan : a) (fog)(x)

= f{ g(x)}

= f(x² -2)

= 3(x² -2)  + 1

= 3x² – 6 + 1

= 3x²- 5

(fog)(x) = 3x² – 1

(gof)(x) =

=g{f(x)}

= g{3x+1}

= (3x+ 1)² – 2

= 9x² + 6x + 1 – 2

= 9x² +6 x – 1

gof(x)= 9x² + 6x – 1

b) (fog)(3)​

=  f { g(3)}

=  f{3²- 2}

=  f(9- 2)

= f (7)

= 3(7)+ 1

= 21 + 1

= 22

fog(3) = 22