The distance of the line x−22=y−63=z−34\frac{x-2}{2}=\frac{y-6}{3}=\frac{z-3}{4} from the point (1,4,0)(1{,}4{,}0) along the line x4=y−22=z+33\frac{x}{4}=\frac{y-2}{2}=\frac{z+3}{3} is:

Answer: The distance is 42218\frac{\sqrt{4221}}{8}.

Step-by-step solution

Step 1: Define the lines and point

We are given two lines, L1L_1 and L2L_2, and a point P0P_0. We need to find the distance from P0P_0 to L1L_1 measured along L2L_2. First, we write the parametric equations for both lines. Let L1L_1 be parameterized by λ\lambda and L2L_2 by μ\mu.

Step 2: Find a general point on L2

Any point on line L2L_2 can be represented by the coordinates (4μ,2μ+2,3μ−3)(4\mu, 2\mu+2, 3\mu-3) by setting each part of the equation for L2L_2 equal to μ\mu. This point will be used to form a line segment from P0P_0 to L1L_1.

Step 3: Find the equation of the line segment from P0 to L1

The line segment connecting P0(1,4,0)P_0(1{,}4{,}0) to a general point P2(4μ,2μ+2,3μ−3)P_2(4\mu, 2\mu+2, 3\mu-3) on L2L_2 has direction vector P0P2⃗\vec{P_0P_2}. This vector represents the line along which we are measuring the distance.

Step 4: Determine the intersection point on L1

The line segment P0P2⃗\vec{P_0P_2} must intersect L1L_1. This means the point P2P_2 must lie on L1L_1. We substitute the coordinates of P2P_2 into the equation for L1L_1 and solve for μ\mu. We equate the first two ratios to find μ\mu.

Step 5: Calculate the coordinates of P2

Now that we have the value of μ\mu, we can find the exact coordinates of the point P2P_2 on L2L_2 that lies on L1L_1. This point P2P_2 is the point on L1L_1 that is reached from P0P_0 by traveling along L2L_2.

Step 6: Calculate the distance between P0 and P2

Finally, we calculate the distance between the point P0(1,4,0)P_0(1{,}4{,}0) and the point P2(−72,14,−458)P_2\left(-\frac{7}{2}, \frac{1}{4}, -\frac{45}{8}\right) using the distance formula in 3D. This distance is the required distance of L1L_1 from P0P_0 along L2L_2.

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