Work Classsssssssssssss

Hey there. so its a work period as you may have gathered from the title. and i am trying to do the practice test for thursday this week. yup test again. i can actually know how to do some of this stuff...like sum/difference identities, finding exact values, making both sides equal the same thing...proving identities i think thats what its called, and double angle identiteis. im not very good at simplifying equations, or using extraneous roots. but at least i can do the majority of these things. awesome.