Differential Equations

$\frac{d^4 y}{d x^4}=0$

$\frac{d^3 y}{d x^3}=0$

$\frac{d^5 y}{d x^5}=0$

$\frac{d^3 y}{d x^3}+\frac{d^4 y}{d x^4}=0$