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Trig functions powers

    • Thread Starter

    I was wondering why sin^2(x) = (sin(x))^2 ​​but sin^-1(x) ≠ (sin(x))^-1 ?

    It's really just because of unfortunate notation.

    sin-1(x) the way you know it means "the inverse of sine" meaning that if sin(a) = b then sin-1(b) = a.

    unfortunately this clashes with when we say sin^2(x) meaning sin(x)^2

    To avoid this you can use arcsin, arccos and arctan (short for arcsine, arccosine and arctangent) meaning "the inverse of sine..." etc

    To write 1/sinx I would either write just that (1/sinx) or sin(x)^-1 to avoid confusion.
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