Find all the points of discontinuity of the greatest integer function defined by `f(x) = [x]`, where [x] denotes the greatest integer less than or equal to x.

Explanation

To find all the points of discontinuity of the greatest integer function defined by \( f(x) = [x] \), where \([x]\) denotes the greatest integer less than or equal to \( x \), we will analyze the function step by step.

### Step 1: Understanding the Greatest Integer Function
The greatest integer function, \([x]\), returns the largest integer that is less than or equal to \( x \). For example:
- \([2.3] = 2\)
- \([3] = 3\)
- \([-1.5] = -2\)

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