How do you solve $sec theta = 4$ ?

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Answer 1 · 2018-05-26T16:42:27

$theta=-arccos(1/4)+2kpi$ or $theta=arccos(1/4)+2kpi$

Since
$sec(x)=1/cos(x)$
we have to solve that
$cos(theta)=1/4$
We get the solutions like above.

Answer 2 · 2018-05-26T17:56:04

$t = +- 75^@52 + k360^@$

sec t = 4 --> $cos t = 1/(sec t) = 1/4 = 0.25$
Calculator and unit circle give 2 solutions for t:
$t = +- 75^@52 + k360^@$

How do you solve sec theta = 4sec theta = 4?