



 
Hi Simran, I want to illustrate using the graph of a function. Suppose $x = 2.5$ then from the graph it looks like $f(x) = f(2.5)$ is approximately $\large \frac12$ and $f(x) = f(2.5)$ is approximately $3 \large \frac{1}{2}.$ Also if $x=5$ then $f(x) = f(5)$ is a little less than $5$ and $f(x) = f(5)$ is a little less than $2 \large \frac{1}{2}.$ The point is that the relationship between $f(x)$ and $f(x)$ depends very much on the value of $x$ and the shape of the graph. I hope this helps,  


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