1. **State the problem:**
We are given a cubic function $h(x) = x^3 - 3x$ representing a water slide profile, and two points $A(2,3)$ and $B(6,9)$ defining a line segment. We want to analyze the line segment $AB$ and find the perpendicular line from the origin $(0,0)$ to this line.
2. **Find the equation of the line passing through points $A$ and $B$:**
The slope $m$ of the line through $A(2,3)$ and $B(6,9)$ is
$$m = \frac{9 - 3}{6 - 2} = \frac{6}{4} = \frac{3}{2}.$$
Using point-slope form with point $A$:
$$y - 3 = \frac{3}{2}(x - 2).$$
Simplify:
$$y = \frac{3}{2}x - 3 + 3 = \frac{3}{2}x.$$
So the line $AB$ has equation:
$$y = \frac{3}{2}x.$$
3. **Find the equation of the perpendicular line from the origin to line $AB$:**
The slope of line $AB$ is $\frac{3}{2}$, so the slope of the perpendicular line is the negative reciprocal:
$$m_\perp = -\frac{2}{3}.$$
Since it passes through the origin $(0,0)$, its equation is:
$$y = -\frac{2}{3}x.$$
4. **Find the point of intersection $P$ between the line $AB$ and the perpendicular line:**
Set the two equations equal:
$$\frac{3}{2}x = -\frac{2}{3}x.$$
Bring all terms to one side:
$$\frac{3}{2}x + \frac{2}{3}x = 0.$$
Find common denominator 6:
$$\frac{9}{6}x + \frac{4}{6}x = \frac{13}{6}x = 0.$$
This implies $x=0$, but $x=0$ corresponds to the origin, which is on the perpendicular line but not on $AB$ (since $y=\frac{3}{2}x$ gives $y=0$ at $x=0$). This suggests the origin lies on the line $AB$ only if $y=0$, but $AB$ passes through $(2,3)$ and $(6,9)$, so origin is not on $AB$.
Re-examining the intersection:
Set
$$\frac{3}{2}x = -\frac{2}{3}x$$
$$\Rightarrow \frac{3}{2}x + \frac{2}{3}x = 0$$
$$\Rightarrow \left(\frac{9}{6} + \frac{4}{6}\right)x = 0$$
$$\Rightarrow \frac{13}{6}x = 0$$
$$\Rightarrow x=0.$$
At $x=0$, $y=0$ for both lines, so the origin is the intersection point.
5. **Check if the origin lies on line $AB$:**
Plug $x=0$ into $y=\frac{3}{2}x$:
$$y=0.$$
So the origin $(0,0)$ lies on line $AB$.
6. **Conclusion:**
The perpendicular line from the origin to line $AB$ is the origin itself, meaning the origin lies on the line $AB$. Therefore, the perpendicular distance from the origin to line $AB$ is zero.
**Final answer:**
- Equation of line $AB$: $$y = \frac{3}{2}x$$
- Equation of perpendicular line from origin: $$y = -\frac{2}{3}x$$
- Intersection point is the origin $(0,0)$, so the origin lies on line $AB$.
- Perpendicular distance from origin to line $AB$ is zero.
Line Perpendicular A5B90B
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