if-f-g-x-2x-5-and-f-x-x-2-find-g-x-

Question Number 148035 by mathdanisur last updated on 25/Jul/21

i f f (g (x)) = 2 x - 5 a n d f (x) = x + 2

f i n d g (x) = ?

Commented by prakash jain last updated on 25/Jul/21

f (x) = x + 2

f (g (x)) = g (x) + 2

g (x) + 2 = 2 x - 5 \Rightarrow g (x) = 2 x - 7

Commented by mathdanisur last updated on 25/Jul/21

T h a n k y o u S e r

Answered by Olaf_Thorendsen last updated on 25/Jul/21

f (x) = x + 2 \Rightarrow f^{'} (x) = 1

f o g (x) = 2 x - 5

\Rightarrow g^{'} (x) \times f^{'} o g (x) = 2

g^{'} (x) \times 1 = 2

g^{'} (x) = 2

g (x) = 2 x + C

f o g (x) = (2 x + C) + 2 = 2 x - 5 \Rightarrow C = - 7

g (x) = 2 x - 7

Commented by mathdanisur last updated on 25/Jul/21

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