The sum of order and degree of the differential equation $\left(x^2\frac{d^2y}{dx^2}\right)^{3/4}= 5(\frac{dy}{dx})^2- 3$ is equal to
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 5
Given differential equation:
$\left(x^{2}\frac{d^{2}y}{dx^{2}}\right)^{\frac{3}{4}} = 5\left(\frac{dy}{dx}\right)^{2} - 3$
To make it a polynomial in derivatives, raise both sides to the power $\frac{4}{3}$:
$x^{2}\frac{d^{2}y}{dx^{2}} = \left(5\left(\frac{dy}{dx}\right)^{2} - 3\right)^{\frac{4}{3}}$
Highest order derivative: $\frac{d^{2}y}{dx^{2}} \Rightarrow$ Order = 2
Degree = 3 (power of highest derivative after removing radicals/fractions)
Sum of order and degree = $2 + 3 = 5$
Sum = 5