I'm not sure if this question is appropriate for this site, so I appologize in advance if it's not.For the purpose of a certain project I am working on, I would like to have the following sets plotted in 3D: $A = \{(x_1,x_2,x_3) \in \mathbb{R}^3 : x_1 \geq x_2, x_3 = 0\}$$B = \{(x_1,x_2,x_3) \in \mathbb{R}^3 : x_1 = x_2 \geq x_3 \geq 0\}$ and$C = \{x \in \mathbb{R}^3 : x_1 \geq x_2 = x_3 \geq 0\}$.Note that these are not subspaces. I do not know any sort of mathematical software, but if someone could let me know how I could plot these sets in 3D in a (preferably free) program then I would appreciate it. You see, I imagine that plotting 3 different hyperplanes would be easy, but the fact that these sets are not hyperplanes (they are triangle shaped, I believe) makes it harder. I would also like to find the angles in each triangle.I just read about gnu-plot. Maybe that could help?Thanks.
Visualizing certain sets
data visualization;plotting