MHB Finding f/g: Composite Functions

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To find the composite function f(g(x)), where f(x)=x^2+1 and g(x)=1/x, the calculation results in f(g(x))=f(1/x)=(1/x)^2+1, which simplifies to 1/x^2+1. Additionally, the quotient of the functions is calculated as f/g(x)=(f(x))/(g(x))=(x^2+1)/(1/x), leading to the expression (x^2+1)x=x^3+x. The discussion clarifies the distinction between composite functions and the quotient of functions. The final results for both operations are provided clearly.
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The questions is asking me to find \frac{f}{g} basically , the question is asking me to find the answer , even though i know it, i can't get my head around it.

the composite function is

f(x)=x^2+1
g(x)=1/x

we need to find foG (f of g) [composite functions].
 
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HelpPlease said:
The questions is asking me to find \frac{f}{g} basically , the question is asking me to find the answer , even though i know it, i can't get my head around it.

the composite function is

f(x)=x^2+1
g(x)=1/x

we need to find foG (f of g) [composite functions].

Thank you solved.Divide them both so x^2+1 / 1/x
switch them to multiply so it's going to be x^2+1/x
 
$f \circ g(x)= f(g(x))=\frac{1}{x^2}+1$
 
Additionally, the quotient (which is not the composite $f \circ g$) is:
$$\frac fg(x) = \frac{f(x)}{g(x)}=\frac{x^2+1}{1/x}=(x^2+1)x=x^3+x$$
 
Just to add an intermediary step:

$$(f\circ g)(x)=f(g(x))=f\left(\frac{1}{x}\right)=\left(\frac{1}{x}\right)^2+1=\frac{1}{x^2}+1$$
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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