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    Just wanted to know how to deal with modulus functions. For example if x<0 and the funtion is y= /x^2-5/+12 how do u find inverse funtion. Also if u have any good modulus questions please post then here.
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    (Original post by Adil Bhai)
    Just wanted to know how to deal with modulus functions. For example if x<0 and the funtion is y= /x^2-5/+12 how do u find inverse funtion. Also if u have any good modulus questions please post then here.
    modulus functions, are just reflected in the x-axis, as there are no negative x values. for the inverse of a function, all yu need to do is swap x for y, and solve for y.
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    With:

    y = |x^2-5| +12

    You can tell that with |x^2 - 5|, the modulus part is only important when it is negative, or when:

    x < √5

    So when x > √5, just draw the graph y = x^2 + 8, as the modulus function has no effect past this point - it is making an already positive expression positive.

    But when x < √5, the (x^2 - 5) part is reflected about the x-axis, then raised by 12 because of the +12 on the end (I think). x^2 will always be positive for real values of x, but when the binomial (x^2 - 5) goes below zero, the modulus makes it positive, therefore whereas if x = 2,

    x^2 - 5:

    2^2 - 5 = -1
    |2^2 - 5| = 1

    So instead of being below the y-axis, it will be the same amount above the y-axis. I think,.
 
 
 
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Updated: June 20, 2004
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