If ` (2sinalpha)/(1+cosalpha +sinalpha)=y` , then prove that `(1-cosalpha+sinalpha )/(1+sinalpha)` is also equal to y.

Explanation

To prove that \( \frac{1 - \cos \alpha + \sin \alpha}{1 + \sin \alpha} = y \) given that \( y = \frac{2 \sin \alpha}{1 + \cos \alpha + \sin \alpha} \), we will follow these steps:

### Step 1: Start with the Left-Hand Side (LHS)
We begin with the expression we want to prove:
\[ \text{LHS} = \frac{1 - \cos \alpha + \sin \alpha}{1 + \sin \alpha} \]

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