Please Do This And Explain It .

Simplify without using calculator leaving your answer in surd form.

sin 480 - cos 765
........................................
tan 225- cos(- 330)

1 answer

add/subtract 360 until you get to an angle you recognize
sin480 = sin120 = sin60 = √3/2
cos765 = cos45 = 1/√2
tan225 = 1
cos -330 = cos30 = √3/2
now plug and chug