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If P(x,y,z) is a point on the line segme...

If `P(x,y,z)` is a point on the line segment joining `Q(2,2,4)` and `R(3,5,6)` such that the projection of `vec(OP)` on the axes are `13/5, 19/5, 26/5` respectively, then `P` divides `QR` in the ratio:

A

`1:2`

B

`3:2`

C

`2:3`

D

`1:3`

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To solve the problem, we need to find the coordinates of point \( P(x,y,z) \) and determine the ratio in which it divides the line segment joining points \( Q(2,2,4) \) and \( R(3,5,6) \). ### Step 1: Identify the coordinates of point \( P \) Given the projections of \( \vec{OP} \) on the axes are: - \( x \)-coordinate: \( \frac{13}{5} \) - \( y \)-coordinate: \( \frac{19}{5} \) - \( z \)-coordinate: \( \frac{26}{5} \) Thus, the coordinates of point \( P \) are: \[ P\left(\frac{13}{5}, \frac{19}{5}, \frac{26}{5}\right) \] ### Step 2: Set up the section formula Let \( P \) divide \( QR \) in the ratio \( k:1 \). According to the section formula, the coordinates of point \( P \) can be expressed as: \[ P = \left( \frac{mx_2 + nx_1}{m+n}, \frac{my_2 + ny_1}{m+n}, \frac{mz_2 + nz_1}{m+n} \right) \] where \( Q(x_1, y_1, z_1) = (2, 2, 4) \) and \( R(x_2, y_2, z_2) = (3, 5, 6) \). ### Step 3: Substitute the coordinates into the section formula Using the section formula, we can write: \[ P\left(\frac{13}{5}, \frac{19}{5}, \frac{26}{5}\right) = \left( \frac{3k + 2}{k+1}, \frac{5k + 2}{k+1}, \frac{6k + 4}{k+1} \right) \] ### Step 4: Set up equations for each coordinate From the \( x \)-coordinate: \[ \frac{3k + 2}{k + 1} = \frac{13}{5} \] Cross-multiplying gives: \[ 5(3k + 2) = 13(k + 1) \] Expanding both sides: \[ 15k + 10 = 13k + 13 \] Rearranging gives: \[ 2k = 3 \implies k = \frac{3}{2} \] ### Step 5: Verify with the \( y \)-coordinate Now, let's check the \( y \)-coordinate: \[ \frac{5k + 2}{k + 1} = \frac{19}{5} \] Substituting \( k = \frac{3}{2} \): \[ \frac{5\left(\frac{3}{2}\right) + 2}{\frac{3}{2} + 1} = \frac{\frac{15}{2} + 2}{\frac{5}{2}} = \frac{\frac{15 + 4}{2}}{\frac{5}{2}} = \frac{\frac{19}{2}}{\frac{5}{2}} = \frac{19}{5} \] This confirms that the \( y \)-coordinate is correct. ### Step 6: Verify with the \( z \)-coordinate Now, let's check the \( z \)-coordinate: \[ \frac{6k + 4}{k + 1} = \frac{26}{5} \] Substituting \( k = \frac{3}{2} \): \[ \frac{6\left(\frac{3}{2}\right) + 4}{\frac{3}{2} + 1} = \frac{9 + 4}{\frac{5}{2}} = \frac{13}{\frac{5}{2}} = \frac{26}{5} \] This confirms that the \( z \)-coordinate is also correct. ### Conclusion Thus, point \( P \) divides the line segment \( QR \) in the ratio: \[ \frac{3}{2} : 1 \quad \text{or} \quad 3 : 2 \]

To solve the problem, we need to find the coordinates of point \( P(x,y,z) \) and determine the ratio in which it divides the line segment joining points \( Q(2,2,4) \) and \( R(3,5,6) \). ### Step 1: Identify the coordinates of point \( P \) Given the projections of \( \vec{OP} \) on the axes are: - \( x \)-coordinate: \( \frac{13}{5} \) - \( y \)-coordinate: \( \frac{19}{5} \) - \( z \)-coordinate: \( \frac{26}{5} \) ...
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