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Consider the planes 3x-6y-2z=15 and 2x+y...

Consider the planes `3x-6y-2z=15 and 2x+y-2z=5.` Statement 1:The parametric equations of the line intersection of the given planes are `x=3+14 t ,y=2t ,z=15 tdot` Statement 2: The vector `14 hat i+2 hat j+15 hat k` is parallel to the line of intersection of the given planes.

A

a. Both the statements are true, and Statement 2 is the correct explanation for Statement 1.

B

b. Both the Statements are true, but Statement 2 is not the correct explanation for Statement 1.

C

c. Statement 1 is true and Statement 2 is false.

D

d Statement 1 is false and Statement 2 is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the line of intersection of the two given planes and analyze the statements provided. ### Step 1: Write down the equations of the planes. The equations of the planes are: 1. \( P_1: 3x - 6y - 2z = 15 \) 2. \( P_2: 2x + y - 2z = 5 \) ### Step 2: Find the normal vectors of the planes. The normal vector of plane \( P_1 \) is \( \vec{n_1} = \langle 3, -6, -2 \rangle \) and for plane \( P_2 \), the normal vector is \( \vec{n_2} = \langle 2, 1, -2 \rangle \). ### Step 3: Find the direction vector of the line of intersection. The direction vector \( \vec{d} \) of the line of intersection of the two planes can be found using the cross product of the normal vectors: \[ \vec{d} = \vec{n_1} \times \vec{n_2} \] Calculating the cross product: \[ \vec{d} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 3 & -6 & -2 \\ 2 & 1 & -2 \end{vmatrix} = \hat{i}((-6)(-2) - (-2)(1)) - \hat{j}((3)(-2) - (-2)(2)) + \hat{k}((3)(1) - (-6)(2)) \] \[ = \hat{i}(12 + 2) - \hat{j}(-6 + 4) + \hat{k}(3 + 12) \] \[ = \hat{i}(14) - \hat{j}(-2) + \hat{k}(15) \] \[ = 14\hat{i} + 2\hat{j} + 15\hat{k} \] ### Step 4: Find a point on the line of intersection. To find a point on the line, we can set \( z = 0 \) and solve the equations: 1. From \( P_1: 3x - 6y = 15 \) 2. From \( P_2: 2x + y = 5 \) Substituting \( z = 0 \) into the equations: 1. \( 3x - 6y = 15 \) simplifies to \( x - 2y = 5 \) 2. \( 2x + y = 5 \) Now we can solve these two equations. From \( x - 2y = 5 \), we can express \( x \) in terms of \( y \): \[ x = 2y + 5 \] Substituting into the second equation: \[ 2(2y + 5) + y = 5 \implies 4y + 10 + y = 5 \implies 5y + 10 = 5 \implies 5y = -5 \implies y = -1 \] Substituting \( y = -1 \) back to find \( x \): \[ x = 2(-1) + 5 = 3 \] Thus, when \( z = 0 \), we have the point \( (3, -1, 0) \). ### Step 5: Write the parametric equations of the line. Using the point \( (3, -1, 0) \) and the direction vector \( \langle 14, 2, 15 \rangle \), the parametric equations of the line are: \[ x = 3 + 14t, \quad y = -1 + 2t, \quad z = 0 + 15t \] ### Step 6: Analyze the statements. - **Statement 1**: The parametric equations of the line intersection of the given planes are \( x = 3 + 14t, y = 2t, z = 15t \). This statement is **false** because the correct equation for \( y \) should be \( y = -1 + 2t \). - **Statement 2**: The vector \( 14\hat{i} + 2\hat{j} + 15\hat{k} \) is parallel to the line of intersection of the given planes. This statement is **true** since it is the direction vector we found. ### Conclusion: The correct option is that Statement 1 is false and Statement 2 is true.

To solve the problem, we need to find the line of intersection of the two given planes and analyze the statements provided. ### Step 1: Write down the equations of the planes. The equations of the planes are: 1. \( P_1: 3x - 6y - 2z = 15 \) 2. \( P_2: 2x + y - 2z = 5 \) ### Step 2: Find the normal vectors of the planes. ...
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Consider the planes 3x-6y-2z-15 =0 and 2x+y-2z - 5=0 Statement 1:The parametric equations of the line intersection of the given planes are x=3+14 t ,y=2t ,z=15 tdot Statement 2: The vector 14 hat i+2 hat j+15 hat k is parallel to the line of intersection of the given planes.

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Knowledge Check

  • A vector parallel to the line of intersection of the planes overset(to)( r) (3 hat(i) - hat(j) + hat(k) )=5 and overset(to) (r ) (hat(i) +4 hat(j) - 2 hat(k) )=3 is

    A
    `2hat(i) + 7 hat(j) -13 hat(k)`
    B
    `2hat(i) - 7hat(i) + 13 hat(k)`
    C
    `-2hat(i) + 7 hat(j) + 13 hat(k)`
    D
    `2hat(i) + 7 hat(j) + 13 hat(k)`
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