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(i) Find the distance of the point (-2,3...

(i) Find the distance of the point (-2,3,-4) from the line :
`(x + 2)/(3) = (2y + 3)/(4) = (3z + 4)/(5),`
measured parallel to the plane `4x +12y -3z +1 = 0. `
(ii) Find the distance of the point `-2hati+3hatj-4hatk` from the line :
`vecr=hati+2hatj-hatk+lambda(hati+3hatj-9hatk)`
measured parallel to the plane `x-y+2z-3=0`

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To solve the given problems step by step, we will break down each part clearly. ### Part (i): Find the distance of the point (-2, 3, -4) from the line given by the equation: \[ \frac{x + 2}{3} = \frac{2y + 3}{4} = \frac{3z + 4}{5} \] measured parallel to the plane \(4x + 12y - 3z + 1 = 0\). **Step 1: Identify the line's direction ratios and a point on the line.** From the line equation, we can express it in parametric form: - Let \( t = \frac{x + 2}{3} = \frac{2y + 3}{4} = \frac{3z + 4}{5} \). This gives us: - \( x = 3t - 2 \) - \( y = 2t - \frac{3}{2} \) - \( z = \frac{5t - 4}{3} \) The direction ratios of the line are \( (3, 2, 5) \). **Step 2: Find the normal vector of the plane.** The normal vector of the plane \(4x + 12y - 3z + 1 = 0\) is given by the coefficients of \(x\), \(y\), and \(z\): - Normal vector \( \mathbf{n} = (4, 12, -3) \). **Step 3: Check if the line is parallel to the plane.** For the line to be parallel to the plane, the direction ratios of the line must be perpendicular to the normal vector of the plane. We check this using the dot product: \[ 3 \cdot 4 + 2 \cdot 12 + 5 \cdot (-3) = 12 + 24 - 15 = 21 \neq 0 \] Since the dot product is not zero, the line is not parallel to the plane. **Step 4: Find the foot of the perpendicular from the point (-2, 3, -4) to the line.** Let \( A(-2, 3, -4) \) be the point and \( B(3t - 2, 2t - \frac{3}{2}, \frac{5t - 4}{3}) \) be a point on the line. The vector \( \overrightarrow{AB} \) is given by: \[ \overrightarrow{AB} = (3t - 2 + 2, 2t - \frac{3}{2} - 3, \frac{5t - 4}{3} + 4) \] This simplifies to: \[ \overrightarrow{AB} = (3t, 2t - \frac{9}{2}, \frac{5t + 8}{3}) \] **Step 5: Set up the equation for perpendicularity.** For \( \overrightarrow{AB} \) to be perpendicular to the line's direction ratios, we set up the equation: \[ 3t \cdot 3 + (2t - \frac{9}{2}) \cdot 2 + (\frac{5t + 8}{3}) \cdot 5 = 0 \] This leads to: \[ 9t + 4t - 9 + \frac{25t + 40}{3} = 0 \] Multiplying through by 3 to eliminate the fraction: \[ 27t + 12t - 27 + 25t + 40 = 0 \] Combining like terms gives: \[ 64t + 13 = 0 \implies t = -\frac{13}{64} \] **Step 6: Find the coordinates of the foot of the perpendicular.** Substituting \( t = -\frac{13}{64} \) back into the parametric equations of the line: \[ x = 3(-\frac{13}{64}) - 2 = -\frac{39}{64} - \frac{128}{64} = -\frac{167}{64} \] \[ y = 2(-\frac{13}{64}) - \frac{3}{2} = -\frac{26}{64} - \frac{96}{64} = -\frac{122}{64} \] \[ z = \frac{5(-\frac{13}{64}) - 4}{3} = \frac{-\frac{65}{64} - \frac{256}{64}}{3} = -\frac{321}{192} \] **Step 7: Calculate the distance from point A to point B.** Using the distance formula: \[ d = \sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2 + (z_2 - z_1)^2} \] Substituting the coordinates of points A and B: \[ d = \sqrt{\left(-\frac{167}{64} + 2\right)^2 + \left(-\frac{122}{64} + 3\right)^2 + \left(-\frac{321}{192} + 4\right)^2} \] Calculating each term gives the final distance. ### Part (ii): Find the distance of the point \(-2\hat{i} + 3\hat{j} - 4\hat{k}\) from the line: \[ \vec{r} = \hat{i} + 2\hat{j} - \hat{k} + \lambda(\hat{i} + 3\hat{j} - 9\hat{k}) \] measured parallel to the plane \(x - y + 2z - 3 = 0\). **Step 1: Identify the direction ratios of the line.** From the line equation, we can see: - The direction ratios of the line are \( (1, 3, -9) \). **Step 2: Find the normal vector of the plane.** The normal vector of the plane \(x - y + 2z - 3 = 0\) is given by the coefficients of \(x\), \(y\), and \(z\): - Normal vector \( \mathbf{n} = (1, -1, 2) \). **Step 3: Check if the line is parallel to the plane.** We check the dot product: \[ 1 \cdot 1 + 3 \cdot (-1) + (-9) \cdot 2 = 1 - 3 - 18 = -20 \neq 0 \] The line is not parallel to the plane. **Step 4: Find the foot of the perpendicular from the point to the line.** Let \( A(-2, 3, -4) \) be the point and \( B(1 + \lambda, 2 + 3\lambda, -1 - 9\lambda) \) be a point on the line. The vector \( \overrightarrow{AB} \) is given by: \[ \overrightarrow{AB} = (1 + \lambda + 2, 2 + 3\lambda - 3, -1 - 9\lambda + 4) \] This simplifies to: \[ \overrightarrow{AB} = (3 + \lambda, -1 + 3\lambda, 3 - 9\lambda) \] **Step 5: Set up the equation for perpendicularity.** For \( \overrightarrow{AB} \) to be perpendicular to the line's direction ratios, we set up the equation: \[ (3 + \lambda) \cdot 1 + (-1 + 3\lambda) \cdot 3 + (3 - 9\lambda) \cdot (-9) = 0 \] This leads to: \[ 3 + \lambda - 3 + 9\lambda + 27 - 81\lambda = 0 \] Combining like terms gives: \[ -71\lambda + 27 = 0 \implies \lambda = \frac{27}{71} \] **Step 6: Find the coordinates of the foot of the perpendicular.** Substituting \( \lambda = \frac{27}{71} \) back into the parametric equations of the line: \[ x = 1 + \frac{27}{71} = \frac{98}{71} \] \[ y = 2 + 3 \cdot \frac{27}{71} = \frac{198}{71} \] \[ z = -1 - 9 \cdot \frac{27}{71} = -\frac{264}{71} \] **Step 7: Calculate the distance from point A to point B.** Using the distance formula: \[ d = \sqrt{\left(\frac{98}{71} + 2\right)^2 + \left(\frac{198}{71} - 3\right)^2 + \left(-\frac{264}{71} + 4\right)^2} \] Calculating each term gives the final distance.
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Find the distance of the point hati+2hatj-hatk from the plane vecr.(hati-2hatj+4hatk)=10

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Find the distance of the point hati + 2hatj - hatk from the plane barr*(hati - 2hatj + 4hatk) = 10 .

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Find the image of the point (3hati-hatj+11hatk) in the line vecr = 2 hatj + 3hatk+lambda(2hati+3hatj+4hatk) .

Find the distance of the point (3,4,5) from the plane vecr.(2hati-5hatj+3hatk)=13

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MODERN PUBLICATION-THREE DIMENSIONAL GEOMETRY -EXERCISE 11 (E) (LONG ANSWER TYPE QUESTIONS (II) )
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  2. Find the ratio in which the line-segment joining the points : (i) (2...

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  3. Find the equation of the plane passing through the point (1,2,1) and p...

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  4. Find the image of the point : (i) (2,-3,2) in the plane 2x + y - 3z ...

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  5. (i) Find the co-ordinates of foot of perpendicular drawn from the poin...

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  6. The foot of the perpendicular drawn from origin to a plane is (4,-2,5)...

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  7. Find the co-ordinates of the foot of the perpendicular Q drawn from P ...

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  8. Find the length and the foot of the perpendicular from the point P(7,1...

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  9. Find the distance of the point P (1,2,3) from its image in the plane x...

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  10. Find the coordinates of the point where the line through (3,-4,-5) and...

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  11. (i) A variable plane, which remains at a constant distance '3p' from t...

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  12. If a plane has intercepts a,b,c on axes and is at a distance of p unit...

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  13. A variable plane passes through a fixed point (a,b,c) and meets the co...

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  14. A variable plane moves in such a way that the sum of the reciprocals o...

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  15. Differentiate e^tanx cosx

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  16. Find the equations of the bisectors of the angles between the plane...

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  17. In the following determine whether the given planes are parallel or pe...

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