Dik f(x)=x^2+4x-5 g(x)=2x-1 tentukan (fog)(x), (fog)(2), (gof)(x), (gof)(2)

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Dik
f(x)=x^2+4x-5
g(x)=2x-1
tentukan (fog)(x), (fog)(2), (gof)(x), (gof)(2)

Fog (x) = (2x – 1 )^2 + 4(2x -1) – 5
= 2x^2 – 4x + 1 + 8x – 4 – 5
= 2x^2 + 4x – 8
Fog (2) = 2(2)^2 + 4(2) – 8
= 8 + 8 – 8
= 8
Gof (x) = 2 ( x^2 +4x – 5 ) -1
= 2x^2 + 8x – 11
Gof (2) = 2(2)^2 + 2(8) – 11
= 8 + 16 – 11
= 13.