hi guys im having a bit of trouble with this 2 questions from my text book.

1. Find the exact value of the expression:

cos(arctan3/4)+tan(arccos3/5)

2. Solve the trig Eq:

2cos^3(x)+5cos^2(x)=2-cos(x)

can you guy please post a worked solution if you can im out of ideas.

thanks