equations

A couple of 8th graders I tutor showed me a quiz they had done poorly on. I ran into a problem that bothered me. There wasn't technically anything wrong with it, I think. But I could see why it would trip up students. Instructions were to solve for x. It was, roughly, 5x + 2 = 5x + 2. Use...

I need to solve a system of 3 differential equations that are all coupled to each other. I think matrices would be the best way to do it, but i need some help. Lets say that the 3 variables are Mx, My, and Mz, and the diffeq setup is: dMx/dt = A*Mx + B*My + C*Mz dMy/dt = D*Mx + E*My + F*Mz...

This is really directed to Tez, although others are welcome to help as well. I was reading in "Exploring Black Holes" (Wheeler/Taylor) than Einstein's General Relativity equations were not derived, but are written down in similar fashion to Newton's equations. Those equations are not in the...