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    • Thread Starter
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    [1/cosθ] - [cosθ] apparently is equal to [1-cos^2θ/cosθ]

    How?
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    Awww man im so academic! I thought you were a teen maths prodidy or summat.


    Gutted.
    • PS Helper
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    PS Helper
    Do you know how to put fractions over a common denominator?

    That's how.

    For example, \dfrac{1}{4} + 4 = \dfrac{1}{4} + \dfrac{4 \times 4}{4} = \dfrac{1 + 4^2}{4} = \dfrac{17}{4}.

    Except here you're working with a function rather than a number.
    • Community Assistant
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    Ignore the trigonometry.

    Can you see why \frac{1}{x} - x = \frac{1}{x} - \frac{x^2}{x} = \frac{1 - x^2}{x} ?
    • Thread Starter
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    (Original post by Mr M)
    Ignore the trigonometry.

    Can you see why \frac{1}{x} - x = \frac{1}{x} - \frac{x^2}{x} = \frac{1 - x^2}{x} ?
    Thank you! Perfect explanation.
 
 
 
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