The partial differential equation \(\frac{{{\partial ^2}\phi }}{{\partial {x^2}}} + \frac{{{\partial ^2}\phi }}{{\partial {y^2}}} + \left( {\frac{{\partial \phi }}{{\partial x}}} \right) + \left( {\frac{{\partial \phi }}{{\partial y}}} \right) = 0\) has
Degree 1 order 2
The highest derivative is second order, so the order is 2. All derivatives occur to the first power in this polynomial differential equation, so the degree is 1.
The Green's function for the differential equation \(\rm\frac{d^2x}{dt^2}\) + x = f(t), satisfying the initial conditions x(0) = \(\rm\frac{dx}{dt}\) (0) = 0, is
G(t, τ) = \(\begin{cases}0 & \text { for } \quad 0<\rm t<\tau \\ \sin (\rm t−\tau) & \text { for } \quad \rm t>\tau\end{cases}\)
The solution of the differential equation when the source f(t) = θ(t) (the Heaviside step function) is
A differential equation is given as x (t + 2) + 3x (t + 1) + 2x (t) =0; x(0) = 0, x(1) = 1. The solution of this equation will be:
If y = \(\rm\left(\frac{1}{x}\right)^x \), then value of \(\rm e^e\left(\frac{d^2 y}{d x^2}\right)_{x=e}\) is:
If \(f\left( x \right) = \frac{{ax + b}}{{cx + d}}\) and f(f(x)) = x then