Question 443665
Recall the method with the 30,60 90 triangle , but this time draw a 45,45,90 triangle.

The sides are 1,1,sqrt(2) in the 45 45 90 triangle.

A,S,T,C

so in q3,q4, sin is negative.

So we look at our reference angles.

the reference angle in q3 is 180

{{{180 + 45 = highlight(225)}}}

the reference angle in q4 is 360

{{{360 - 45 = highlight(315)}}}

Since you have an infinite amount of angles (since you can add 360 each time), we could express our answer as:

{{{225 + 360n}}}
{{{315 + 360n}}}