Changes

<h3>3. Area</h3>

<h3>3. Area</h3>

Any integral that contains the same upper and lower limit is equal to zero.

Any integral that contains the same upper and lower bounds are equal to zero.

*<math>\int_{a}^{a}f(x)dx=0</math>  

*<math>\int_{a}^{a}f(x)dx=0</math>