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Modulus quick question

What's the difference between y = |f(x)| and y = f|(x)|
Quick google search gives
https://www.thestudentroom.co.uk/showthread.php?t=4400526
https://www.examsolutions.net/tutorials/graphing-yfx/
https://www.examsolutions.net/tutorials/graphing-yfx-2/

Here are videos to help
https://www.youtube.com/watch?v=1WgWI3QIqKY
https://www.youtube.com/watch?v=-kbls98IuBc
https://www.youtube.com/watch?v=dI5uXaDzd4A

In my opinion, watching these videos will help you understand the topic
Original post by Hollymae764
What's the difference between y = |f(x)| and y = f|(x)|

Hi! :smile:
In the first instance, you are applying the modulus to the function of x.
Suppose we have f = x+1 as wish to calculate y at x=-3 for example. We'd first calculate f(x), which in this case is:
f(-3) = -3 + 1 = -2.
Then, we apply the modulus sign so:
y = |f(x)| = |-2| = 2.

For the second inatance, we apply the modulus to x first. So, using the same function and value of x as above:
y = f|(-3)| = f(3) = 3 + 1 = 4.

I hope this makes sense. :h:
(edited 3 years ago)
Original post by Hollymae764
What's the difference between y = |f(x)| and y = f|(x)|

When you have the graph of y=f(x) then;

-- for y = |f(x)| you consider the parts of f(x) which are below the x-axis. Reflect these in the x-axis.

-- for y = f(|x|) you delete the portion of f(x) which is to the left of the vertical axis, and reflect the remaining plot in the y-axis to fill in the deleted space.

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