Question

Se f(x) : 5x + 2k e g(x) : 3x - 12, calcule o valor de k, sabendo que f(g(x)) : G(f)x)).

Answer 1

f(g(x))=g(f(x))
f(x)=3x+4
g(x)=2x+2k
f(g(x))=3.(2x+2k)+4
f(g(x))=6x+6k+4
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g(f(x))=2.(3x+4)+2k
g(f(x))=6x+8+2k
6x+6k+4=6x+8+2k
6x-6x+6k-2k=8-4
4k=4
k=4/4
k=1 #