How do you evaluate using a calculator of $cos^-1(-0.3218)$ ?

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Answer 1 · 2016-09-03T23:57:53

$cos^-1 (-0.3218) = 108.77°$
$cos^-1 (-0.3218) = 251.23°$

You key it in exactly as it is written.

Use the shift/alt/2nd F key before the cos key, to use $cos^-1$

This is not the same as $1/cos$

$cos^-1$ is the way of finding which angle has a cos value of $-0.3218$

$cos^-1 (-0.3218) = 108.77°$

or $cos^-1 (-0.3218) = 251.23°$

How do you evaluate using a calculator of cos^-1(-0.3218)cos^-1(-0.3218)?