Hello,

You should recognize some things :

Every quoted function is 360-periodic.

f(-150)=f(-150+360)=f(210)=f(180+30)

f(-330)=f(-330+360)=f(30)

f(-210)=f(-210+360)=f(150)=f(180-30)

f(-450)=f(-450+360)=f(-90)

etc...

Use the definitions of the functions or the chart to find the values. Always try to get to known values, only by additions and substractions.