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# Integral of modulus watch

1. Is the magnitude of the area between the graph and the x-axis given by the integral with respect to x of the modulus of the equation of the graph? e.g. While the integral of the normal equation would sum the area over the x-axis and subtract the area beneath it, the integral of the modulus of the equation sums the area over the x-axis and adds this to the area beneath it.
Is the magnitude of the area between the graph and the x-axis given by the integral with respect to x of the modulus of the equation of the graph? e.g. While the integral of the normal equation would sum the area over the x-axis and subtract the area beneath it, the integral of the modulus of the equation sums the area over the x-axis and adds this to the area beneath it.
Yes, this is correct.

Hence, to work out the integral of the modulus of a function, you need to:

Find all points of intersection with the chosen axis (x), omitting points of inflection.

Find weather each region lies below or above the chosen axis (x).

Split the integral into a series of integrals that alternates between positive and negative (taking care to adjust the limits correctly).

3. (Original post by Jkn)
Yes, this is correct.

Hence, to work out the integral of the modulus of a function, you need to:

Find all points of intersection with the chosen axis (x), omitting points of inflection.

Find weather each region lies below or above the chosen axis (x).

Split the integral into a series of integrals that alternates between positive and negative (taking care to adjust the limits correctly).

Thanks, yes, I knew the process, I just wanted to find out if it corresponded directly with the "integral of the modulus" (because my calculator can integrate the modulus directly and as a back-up in case I'm running out of time this is very useful).
Thanks, yes, I knew the process, I just wanted to find out if it corresponded directly with the "integral of the modulus" (because my calculator can integrate the modulus directly and as a back-up in case I'm running out of time this is very useful).
Okay, no worries. It's a very useful thing to know
5. (Original post by Jkn)
Find weather each region ...
Apologies for hijacking someone else's thread, but I know you're usually very particular about the use of language (not to mention an A level English student!) and I've spotted this about 4 times in your threads now without saying anything:

'weather' = sun/rain/snow etc

I think the word you want is 'whether'
6. (Original post by davros)
Apologies for hijacking someone else's thread, but I know you're usually very particular about the use of language (not to mention an A level English student!) and I've spotted this about 4 times in your threads now without saying anything:

'weather' = sun/rain/snow etc

I think the word you want is 'whether'
Well that's embarrassing

Rest assured, I do know that! I think I type too quickly Thanks!

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