MaplePrimes - answers and comments on Question, How do i plot a graph with multiple variables?

plot3D

Oliver K — Thu, 22 Nov 2012 20:18:09 Z

restart:c:=50;beta:=10;A:=0.01;L:=0.5;
y:= A*exp(-beta*(x-L-c*t)^2/(L^2));
plot3d(y,x=0..1.5,t=0..0.003,axes=framed,grid=[80,80]);

Adri van der Meer — Thu, 22 Nov 2012 20:21:47 Z

Enter the function y(x,t) as

Y := (x,t) -> A*exp(-beta*(x-L-c*t)^2/(L^2));

(exp(x), not e^x; c*t, not ct)
and the differential equation as

 DE := diff(y(x,t),t,t) = c^2*diff(y(x,t),x,x);

Now evaluate DE for y(x,t)=Y(x,t).

jam — Fri, 23 Nov 2012 16:15:39 Z

I have tried differentiating Y(x,t) with respect to both x and t but I keep getting my answers as zero!

Is this right?

jam — Fri, 23 Nov 2012 16:47:31 Z

Ignore the coment above.

What other commands could you use other than simplify to make the whole equation equal zero?

Adri van der Meer — Fri, 23 Nov 2012 21:06:10 Z

@jam to test if the left hand side of an equation equals the right hand side you can use ?evalb (after simplify).