Question

DOES ANYONE KNOW MATHEMATICA?????

Answer 1

YES

Answer 2

what's your question , sailor?

Answer 3

okay: i need to use derivative to verify that : p(x,t) = (1/(Sqrt[4 Pi t])) Exp[ -x^2/(4 t)
is the solution of the diffusion equation dp/dt= d^2p/dx^2

Answer 4

i got the value for dp/dt with the function :pt = D[(1./(Sqrt[4 Pi t])) Exp[ -x^2/(4 t)], t]

Answer 5

but my second derivative of dx gives me 0.

Answer 6

dx = D[(1./(Sqrt[4 Pi t])) Exp[ -x^2/(4 t)], {x, 2}]
is there soemthign wrong with my equation?

Answer 7

:(

Answer 8

so are you trying to solve differential equation or take second derivative?

Answer 9

second derviative goes like this

D[ Type function here ,{x,2}]

Answer 10

ya thats what i did

Answer 11

D[(1./(Sqrt[4 Pi t])) * Exp[ -x^2/(4 t)], {x, 2}]

Answer 12

./ is not used in mathematica, it is matlab notation

Answer 13

./ i was just trying to make the whole thing into a number so i tried to multiple (dividde) by 1. lol