Correct Answer: 1
Explanation:
The given differential equation is:
$\displaystyle \frac{d}{dx}\left(\frac{dy}{dx}\right)^3 = 0$
Step 1: Expand the derivative
$\displaystyle \frac{d}{dx}\left(\frac{dy}{dx}\right)^3 = 3\left(\frac{dy}{dx}\right)^2 \frac{d^2y}{dx^2} = 0$
Step 2: Identify order and degree
Step 3: Compute $(p - q)$
$(p - q) = 2 - 1 = 1$
∴ Final Answer: $(p - q) = 1$