Evaluate `int_(0)^(1)x^(2)dx` as the limit of a sum.

Explanation

To evaluate the integral \( \int_{0}^{1} x^2 \, dx \) as the limit of a sum, we can follow these steps:

### Step 1: Define the function and limits
We have the function \( f(x) = x^2 \) and we want to evaluate the integral from \( a = 0 \) to \( b = 1 \).

### Step 2: Determine the width of each subinterval
The width of each subinterval \( h \) is given by:
\[
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