Question

s

Answer 1

Do you have a scientific calculator..?

ok... so for the 1st question find

\[\cos^{-1}(\frac{2\sqrt{2}}{2})\]

this an exact value.....

then because its negative, its in the 2nd quadrant.

so you are looking at an angle of

\[Angle = \pi - answer\]

The next question just look at the cos curve



last question is very similar to the 1st

2nd quadrant...

find the exact value of the positive then subtract the answer from pi.