f(x)=3x+c g(x)=cx+8 fg(x)=6x+d Work out c and d.

fg(x) means f of g of x

fg(x) = 3(cx+8) + c = 3cx + 24 + c = 6x + d

3cx = 6x 3c=6 c=2

24 + c = d 24+2=d=26

CF

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