User:Rahul25chandel/sandbox


 * $$\frac{\partial \varphi}{\partial t}(\varphi,t) = F(\varphi).~$$
 * $$\frac{\varphi^{n+1} - \varphi^{n}}{\Delta t} = F(\varphi),$$
 * $$\frac{3\varphi^{n+1} - 4\varphi^{n}+\varphi^{n-1}}{2\Delta t} = F(\varphi),$$

where φ= a scalar quantity

n+1= value at the next time level,t+Δt

n = value at the current time level,t

n-1 = value at the previous time level ,t-Δt


 * $$\frac{\varphi^{n+1} - \varphi^{n}}{\Delta t} = F(\varphi^n+1),$$