Given that f(x)=x^2+2 and g(x)=2x-5, find each of the following.
(FoG)(1) and (GoF)(-3)
(FoG)(1) and (GoF)(-3)
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(FoG)(1) = f(g(1)) = (2(1)-5)^2 + 2 = 11
(GoF)(-3) = g(f(-3)) = 2((-3)^2 + 2) - 5 = 17
(GoF)(-3) = g(f(-3)) = 2((-3)^2 + 2) - 5 = 17
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f(x) = x^2 + 2
g(x) = 2x - 5
f o g)(x) = f(g(x))
to find (f o g)(1) or f(g(1)), evaluate g(1), then substitute that value into f(x)...
g(1) = - 3
f(- 3) = 11
(f o g)(1) = - 11
you try to do (g o f)(- 3)
read your textbook...practice.
[(g o f)(- 3) = g(f(- 3)) = 17]
g(x) = 2x - 5
f o g)(x) = f(g(x))
to find (f o g)(1) or f(g(1)), evaluate g(1), then substitute that value into f(x)...
g(1) = - 3
f(- 3) = 11
(f o g)(1) = - 11
you try to do (g o f)(- 3)
read your textbook...practice.
[(g o f)(- 3) = g(f(- 3)) = 17]
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I'm not exactly sure about your notation,
but:
f(g(1)) = (2(1)-5)^2 + 2 = 11
g(f(-3)) = 2((-3)^2+2)-5 = 6
but:
f(g(1)) = (2(1)-5)^2 + 2 = 11
g(f(-3)) = 2((-3)^2+2)-5 = 6
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g(1) = - 3; f(-3) = 9 + 2 = 11
(f o g)(1) = f(g(1)) by definition of f o g; so (fog)(1) = 11
Same idea:
f(-3) = 11; g(11) = 22 - 5 = 17
(gof))(-3) = g(f(-3)) = g(11) = 17
(f o g)(1) = f(g(1)) by definition of f o g; so (fog)(1) = 11
Same idea:
f(-3) = 11; g(11) = 22 - 5 = 17
(gof))(-3) = g(f(-3)) = g(11) = 17
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(FoG)(1)=11 , (GoF)(-3)=17