If $y = 3e^{2x} + 2e^{3x}$, then $\frac{d^2y}{dx^2}+6y$ is equal to |
$5\frac{dy}{dx}$ $6\frac{dy}{dx}$ $-5\frac{dy}{dx}$ $y^2$ |
$5\frac{dy}{dx}$ |
The correct answer is Option (1) → $5\frac{dy}{dx}$ Given: $y = 3e^{2x} + 2e^{3x}$ First derivative: $\frac{dy}{dx} = 6e^{2x} + 6e^{3x}$ Second derivative: $\frac{d^2y}{dx^2} = 12e^{2x} + 18e^{3x}$ Now compute: $\frac{d^2y}{dx^2} + 6y$ $= 12e^{2x} + 18e^{3x} + 6(3e^{2x} + 2e^{3x})$ $= 12e^{2x} + 18e^{3x} + 18e^{2x} + 12e^{3x}$ $= 30e^{2x} + 30e^{3x}$ $= 6(5e^{2x} + 5e^{3x})$ $= 5(6e^{2x} + 6e^{3x})$ $= 5 \cdot \frac{dy}{dx}$ |