Whether the \( p\text{-}n \) junction diode is forward biased or reverse biased in the given figure.
The diode is reverse biased.
Step 1: In the given circuit, the negative terminal (\(-5V\)) is connected to the \( p \)-side, and the positive terminal (\(-3V\)) is connected to the \( n \)-side.
Step 2: Since the \( p \)-side is at a lower potential, the junction is reverse biased. \[ \boxed{\text{Reverse biased}} \]
(b) Order of the differential equation: $ 5x^3 \frac{d^3y}{dx^3} - 3\left(\frac{dy}{dx}\right)^2 + \left(\frac{d^2y}{dx^2}\right)^4 + y = 0 $