A function `f(theta)` is defined as : `f(theta) = 1 - theta+(theta^2)/(2!) - (theta^3)/(3!) +(theta^4)/(4!)….` why is it necessary for `theta` to be a dimensionless quantity ?

Explanation

To understand why it is necessary for \( \theta \) to be a dimensionless quantity in the function \( f(\theta) \), we can analyze the function step by step.

### Step-by-Step Solution:

1. **Understanding the Function**:
The function is given as:
\[
f(\theta) = 1 - \theta + \frac{\theta^2}{2!} - \frac{\theta^3}{3!} + \frac{\theta^4}{4!} - \ldots
...