Im stuck on 2 problems:
1. cos2x(2cos+1) (I dont know even where to start)
and
tan3x=1this one im beter off on
i relize that tan=1 on (pie/4)
diveded by three for the three rotations you get (pie/12)
i know the answers are (pie/12 + pie N) the book says they are (pie/12, 9pie/12, 17pie/12, 5pie/12, 13pie/12, 21pie /12) how did it get these
thanks
Now, this is a reference angle. So actually we have the 2 equations:
(We ignore quadrants II and IV since tangent is negative there.)
So and .
Now, we are dividing by 3 so there should be 3 solutions associated with each x solution we have. (This is because we can add multiples of to each solution for 3x.)
And this generates the list you gave as a solution.
-Dan