I was trying to remove half angles in an expression. And it seems simplify() does not like to multiply out square root.
sage:theta=var('theta')
sage:assume(theta,'real')
sage:assume(theta>0)
sage:assume(theta<pi)< p="">
sage:m=((sin((1/2)theta)cos((1/2)*theta)).trig_expand(half_angles=True))
sage:view(m.simplify_full())
The output I get is $\frac{1}{2}\sqrt{-\cos\left(\theta\right) + 1} \sqrt{\cos\left(\theta\right) + 1}$
Is there a way I can make sage multiply out the the expression and give me $(1/2)sin \theta$