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F f(x) = 3x + 2 and g(x) = x2 + 1, which expression is equivalent to (f circle g) (x)?

User Salman Kazmi
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1 Answer

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18 votes

hi

f°g mean apply g(x) and then use result of g(x) as "x" in f(x)

so as g(x) = x² +1 and f(x) = 3x+2

so if we call g(x) X we have

f( X) = 3 X +2

now we replace " X" for it's value

f(X) = 3 ( x² +1) +2

f(X) = 3x² +3 +2

f(X) = 3x² +5

so f°g = 3x² +5

User Mbuechmann
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