Integral of 1/x = ln|x|, why absolute?

1. Try dragging points [i]P[/i] and [i]Q[/i], can you describe their relationship?[br]2. What if the [i]x[/i]-coordinate of point [i]Q[/i] is negative?
– maew lee

정보: Integral of 1/x = ln|x|, why absolute?