reyhanadp
(2x+4)^2 = 4x^2+16x+16, It is not like that??
Kochammatmę
Yes, and look that (2x+4)^2 = 4x^2+16x+16 and (f o g)(x)=4x^2+16x-3 have the same "4x^2+16" so you have to change (f o g)(x)=4x^2+16x+16-19 because 16-19 = -3 :)
therefore (f o g)(x) = (2x+4)^2 - 19
now change expression "2x+4" on "x" and THAT'S IT!
f(x) = x^2 - 19 :)
Kochammatmę
f(x) = x^2-19 and g(x) = 2x+4
(f o g)(x) = (2x+4)^2-19 = ... = 4x^+16x - 3
Now understand?:)
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