Posted by VesaN on .
cosxsinx<1/2

equation trig 
bobpursley,
square both sides
cos^2 2sin*cos + sin^2<1/4
1sin(2x)<1/4
sin(2x)<3/4
2x>131deg
x>65.5 deg
2x<311
x<155 check that with a graph. 
equation trig 
VesaN,
thnx