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# What's the difference between |f(x)| and f|(x)|? watch

1. Hi,
Can anyone help me understand the difference between the graphs of y= |f(x)| and y=f|(x)|, please? I understand that for y=|f(x)| you just reflect the parts of the graph below the x axis in the x axis as with any modulus graph, but I don't understand how y=f|(x)| is different- I feel like it should just be the same?
2. Scroll down to modulus functions and equations youll see your two graphs you have stated there

http://www.examsolutions.net/a-level.../c3-tutorials/
Scroll down to modulus functions and equations youll see your two graphs you have stated there

http://www.examsolutions.net/a-level.../c3-tutorials/
Thank you so much!
4. (Original post by panic!intheexam)
Hi,
Can anyone help me understand the difference between the graphs of y= |f(x)| and y=f|(x)|, please? I understand that for y=|f(x)| you just reflect the parts of the graph below the x axis in the x axis as with any modulus graph, but I don't understand how y=f|(x)| is different- I feel like it should just be the same?
y=f |x|
and

y= |f(x)|

are 2 different things

the first is just the modulus of the x and x only

second is modulus of the whole thing
5. (Original post by panic!intheexam)
Hi,
Can anyone help me understand the difference between the graphs of y= |f(x)| and y=f|(x)|, please? I understand that for y=|f(x)| you just reflect the parts of the graph below the x axis in the x axis as with any modulus graph, but I don't understand how y=f|(x)| is different- I feel like it should just be the same?
Note the syntax for a function of x is f(x)

You can either take the modulus before applying the function, f(|x|), or after applying the function |f(x)|.

But the symbol combinations, f|(x)|, and f|x| are meaningless mathematically.

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