How do you write the equation $cos α = 0.5$ $cosalpha=0.5$ in the form of an inverse function?

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Answer 1 · 2018-02-28T15:34:11

We need to solve for $α$ $alpha$

$cos α = 0.5$ $cosalpha = 0.5$

we need to "undo" $cos$ $cos$ . To do that,w e apply it's inverse, $a r c c o s$ $a r c c o s$ or ${cos}^{- 1}$ $cos^-1$

${cos}^{- 1} (cos α) = {cos}^{- 1} (0.5)$ $cos^-1(cosalpha) = cos^-1(0.5)$

$α = {cos}^{- 1} (0.5)$ $alpha = cos^-1(0.5)$

We can solve this, which gives us that $α = \frac{π}{3}$ $alpha = pi/3$ or $5 \frac{π}{3}$ $5pi/3$

How do you write the equation cosα=0.5cosalpha=0.5 in the form of an inverse function?