$\int\limits_1^4|x - 2|dx$ is equal to
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $\frac{5}{2}$
$\displaystyle \int_{1}^{4} |x-2|\,dx$
Break at $x=2$:
$|x-2|=2-x$ for $1\le x\le 2$
$|x-2|=x-2$ for $2\le x\le 4$
$\int_{1}^{2} (2-x)\,dx + \int_{2}^{4} (x-2)\,dx$
$\left[2x-\frac{x^{2}}{2}\right]_{1}^{2} + \left[\frac{x^{2}}{2}-2x\right]_{2}^{4}$
$\left(4-2\right)-\left(2-\frac{1}{2}\right) + \left(8-8\right)-\left(2-4\right)$
$2 - \frac{3}{2} + 0 + 2$
$\frac{1}{2} + 2$
$\frac{5}{2}$
Final answer: $\frac{5}{2}$