Hello, which functions work together with assume (contexts?). I am not able to use solve and assume, what am I doing (thinking) wrong? (%i2) (%i2) assume(a>0); (%o2) [a > 0] (%i3) (%i3) solve( a^2 = 4, a); (%o3) [a = - 2, a = 2] Regards, Robert