Indicate the order of each of the following differential equations :
`y'+3y=0`

Answer

To determine the order of the given differential equation \( y' + 3y = 0 \), we will follow these steps:

### Step 1: Identify the Derivative
The equation given is \( y' + 3y = 0 \). Here, \( y' \) represents the first derivative of \( y \) with respect to \( x \).

### Step 2: Rewrite the Derivative
We can express \( y' \) as \( \frac{dy}{dx} \). Thus, the equation can be rewritten as:
\[ \frac{dy}{dx} + 3y = 0 \]

### Step 3: Determine the Order
The order of a differential equation is defined as the highest derivative present in the equation. In our case, the highest derivative is \( \frac{dy}{dx} \), which is the first derivative.

### Conclusion
Since the highest derivative present is the first derivative, the order of the differential equation \( y' + 3y = 0 \) is:
\[ \text{Order} = 1 \]