trig
posted by please help now .
Solve for x if sin2x=cos(x+60 and x€ [90,180].show all work details

What does x€ [90,180] mean?
The domain limits of x?
You seem to have omitted a parenth after x+60
cos(x+60) = sin(90x60)
= sin (30x)
sin2x = sin(30x)
Therefore 2x = 30 x
x = 10 degrees is one solution
See if you can find others. Note that sin2x = sin(180 2x); that will lead to another solution. 
Yes it mean domaim limit of x that guied u when plot the graph