Algebra/algebra

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Expert: - 9/15/2010


Question
Solve the equation for x.  arccos x = arcsec x

Answer
This is the same as saying cos(arccos x) = cos(arcsec x).
That can be seen to be x = cos(arcsec x).

If arcsec x is y, then the hypotenuse is y and the near side is 1.
The cos of this angle is 1/y.  This says that x = 1/y.

Now since x is a cos(), |x|<=1.

Since y is a hypotenuse on a triangle with side 1, y>=1.
The only way to satisfy this inequality
is to have x and y both be 1 or -1.

The angles that this occurs at are 0° ± n*180°
where n is any integer.

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Scott A Wilson

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Any algebraic question you've got, like linear, quadratic, exponential, etc.

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solving story problems solving linear, parabolic, and 3rd order equations solving equations with multiple variables

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