1. The problem statement, all variables and given/known data a) 2sin3x=sqrt(2). Find Theta. b) Cos4x=1/2. Find Theta 2. Relevant equations 3. The attempt at a solution a) sin3x=1/sqrt(2) Theta=pi/4. This is from the 45-45-90 triangle. Also Theta=3pi/4. How did they get this one? Can you guess it without looking at the graph of the sine function? b) 4x=1/2=pi/3=theta. From 30-60-90 triangle. But theta also equals 5pi/3. Again, How can we guess the other angle( 5pi/3) without looking at the graph of the cosine function? Thanks.