Concept:
• Order of a differential equation is the order of the highest derivative occurring in it.
• Degree of a differential equation is the power of the highest order derivative when the equation is expressed as a polynomial in its derivatives.
Step 1: Identify the highest order derivative
Look at the terms involving derivatives in the equation:
\[ y = \left( \frac{d^2y}{dx^2} \right)^2 - \lambda \left( \frac{dy}{dx} \right) \]
The derivatives present are \( \frac{d^2y}{dx^2} \) (second order) and \( \frac{dy}{dx} \) (first order).
The highest order is 2. So, Order = 2.
Step 2: Determine the degree of the equation
Identify the term containing the highest order derivative, which is \( \left( \frac{d^2y}{dx^2} \right)^2 \).
The power to which this highest order derivative is raised is 2.
Since the equation is already in polynomial form with respect to derivatives (no fractional powers or derivatives inside transcendental functions), this power is the degree.
So, Degree = 2.