How do you do simplify $cos [{sec}^{- 1} (- 5)]$ $cos [sec ^-1 (-5)]$ ?

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How do you do simplify $cos [{sec}^{- 1} (- 5)]$ $cos [sec ^-1 (-5)]$ ?

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Answer 1 · 2015-11-06T04:59:09

$- \frac{1}{5}$ $-1/5$

Explanation:

$cos [{sec}^{- 1} (- 5)]$ $cos[sec^-1(-5)]$

Finding the value of the Composition:

Lets being to solve the equation by working on the inside. Immediately we can see that ${sec}^{- 1} (\frac{5}{- 1})$ $sec^-1(5/(-1))$ isn't a special angle. If you noticed how I attached the negative sign to "1" is because sec = $\frac{r}{x}$ $r/x$ . The radius can not be negative. and "1" serves as the x-value in this equation.

Note: The inverse of cosine (secant) is restricted between $0 < x < π$ $0 < x < pi$ . (This would matter if it were asking for sin instead of cos because the y-value would become negative and give you a wrong answer).
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Now cosine is $\frac{x}{r}$ $x/r$ . So simply put the values where they belong.

$cos (\frac{- 1}{5})$ $cos((-1)/5)$ = $- \frac{1}{5}$ $-1/5$

This is not a special angle so leave the answer as a improper fraction or decimal. Whatever your instructor prefers. :)

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How do you do simplify $cos [{sec}^{- 1} (- 5)]$ $cos [sec ^-1 (-5)]$ ?

1 Answer

Explanation:

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How do you do simplify cos [sec ^-1 (-5)]cos[sec−1(−5)]cos [sec ^-1 (-5)]?

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How do you do simplify $cos [{sec}^{- 1} (- 5)]$ $cos [sec ^-1 (-5)]$ ?