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  • 1 Post By HallsofIvy

Math Help - absolute value with sinθ

  1. #1
    Junior Member
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    absolute value with sinθ

    I encountered an question of calculation of volume.
    The following is a part of the solution.
    I don't know why the highlighted sinθ has an absolute value sign.
    Can anyone explain to me? Thank you.

    absolute value with sinθ-absolute_value.jpg
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  2. #2
    MHF Contributor

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    Re: absolute value with sinθ

    Because \sqrt{a^2}= |a|, not a.

    For example, \sqrt{(-2)^2}= \sqrt{4}= 2, not -2.
    Thanks from happymatthematics
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  3. #3
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    Re: absolute value with sinθ

    Thank you, HallsofIvy.
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