Input: dsolve(ds(y,t)=ds(y,x,2)-ds(y,x))
Write: `dsolve(ds(y,t)=ds(y,x,2)-ds(y,x))`
Output: $$ dsolve(\frac{d}{dt} y=\frac{d^{{2}}y}{dx^{{2}}}-\frac{d}{dx} y) == C_3+C_1\ exp(x)+C_3\ (t-x) $$ Result:$$C_3+C_1\ exp(x)+C_3\ (t-x)$$