httpss3amazonawscomieduattachmentsquestion7a363ea9123465cc96

https://s3.amazonaws.com/iedu-attachments-question/7a363ea9123465cc9619777b69483138_facdb11b633b0c135e4040ee1293de35.jpg could someone help me with any of the problems not crossed out. I just need to see the work to understand it

Solution

2)cot(2pi/3)

cot(pi -(pi/3))

=-tan(pi/3)

=-3

3)sec(180⁰)

=1/cos(180^o)

=1/(-1)

=-1

5)tan(pi/2 +)

tan(pi/2) =infinity , if we use tan(alpha -beta) formula we get infinity/infinity form

tan(pi/2 +)=-cot

6)cos =-4/5

pi/2 <<pi

pi<2<2pi

cos(2)=2cos² -1

cos(2)=2(-4/5)² -1

cos(2)=(32/25) -1

cos(2)=7/25