Question

I was taught how to do this but I need help, as I’m having a brain malfunction

Answer 1

Answer:

theta = 135+ n360

theta = 225+n360

Step-by-step explanation:

-sqrt(2) = 2 cos theta

Divide each side by 2

-sqrt(2)/2 =2/2 cos theta

-sqrt(2)/2 = cos theta

Take the inverse cos on each side

arccos (-sqrt(2)/2) =  arc cos(cos theta)

135 = theta

Now remember this only gives you the value between 0 and 180 degrees.

Take 360 minus the value found to get the other angle since this is cosine

360 -135 = 225

Now remember this is cyclical, so we can add 360 to each of these values and we will get the same amount

theta = 135+ n360

theta = 225+n360