When a portion of the curve $y = f(x)$ lies below the $x$-axis between $x = a$ and $x = b$, the area enclosed there is found by taking which of the following?

1. Below the $x$-axis $f(x) < 0$, so $\int_a^b f(x)\,dx$ comes out negative. 2. Area is a physical magnitude and cannot be negative. 3. Hence we report its numerical value, $\left|\int_a^b f(x)\,dx\right|$. _Source: NCERT Class 12 Mathematics Ch 8 "Application of Integrals", p.1_