I need the answer to #3, I’ve worked everything out and I don’t need an explanation, just the answer. Thanks

Question

asked Oct 21, 2023 169k views

1 Answer

Little Pony · Answer 1 · 2023-10-25T07:51:45+0000

$7\sec ^2-7=0$

Divide both sides by 7:

$\sec ^2(x)-1=0$

Add 1 to both sides:

$\sec ^2=1$

Express sec(x) as 1/cos(x):

$\begin{gathered} (1)/(\cos ^2(x))=1 \\ \cos ^2(x)=1 \\ x=\pi n_{\text{ }};_{\text{ }}n\in\Z \end{gathered}$

Since the solutions are for the interval:

$\lbrack0,2\pi)$

The solutions are:

$x=0,\pi$