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vec(r )=(-4hat(i)+4hat(j) +hat(k)) + lam...

`vec(r )=(-4hat(i)+4hat(j) +hat(k)) + lambda (hat(i) +hat(j) -hat(k))`
`vec(r)=(-3hat(i) -8hat(j) -3hat(k)) + mu (2hat(i) +3hat(j) +3hat(k))`

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To find the shortest distance between the two lines given by the vector equations: 1. **Line 1**: \(\vec{r_1} = (-4\hat{i} + 4\hat{j} + \hat{k}) + \lambda(\hat{i} + \hat{j} - \hat{k})\) 2. **Line 2**: \(\vec{r_2} = (-3\hat{i} - 8\hat{j} - 3\hat{k}) + \mu(2\hat{i} + 3\hat{j} + 3\hat{k})\) We will use the formula for the shortest distance \(d\) between two skew lines: \[ d = \frac{|(\vec{a_2} - \vec{a_1}) \cdot (\vec{b_1} \times \vec{b_2})|}{|\vec{b_1} \times \vec{b_2}|} \] Where: - \(\vec{a_1} = -4\hat{i} + 4\hat{j} + \hat{k}\) - \(\vec{a_2} = -3\hat{i} - 8\hat{j} - 3\hat{k}\) - \(\vec{b_1} = \hat{i} + \hat{j} - \hat{k}\) - \(\vec{b_2} = 2\hat{i} + 3\hat{j} + 3\hat{k}\) ### Step 1: Calculate \(\vec{a_2} - \vec{a_1}\) \[ \vec{a_2} - \vec{a_1} = (-3\hat{i} - 8\hat{j} - 3\hat{k}) - (-4\hat{i} + 4\hat{j} + \hat{k}) \] Calculating this gives: \[ \vec{a_2} - \vec{a_1} = (-3 + 4)\hat{i} + (-8 - 4)\hat{j} + (-3 - 1)\hat{k} = \hat{i} - 12\hat{j} - 4\hat{k} \] ### Step 2: Calculate \(\vec{b_1} \times \vec{b_2}\) Using the determinant method for the cross product: \[ \vec{b_1} \times \vec{b_2} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 1 & 1 & -1 \\ 2 & 3 & 3 \end{vmatrix} \] Calculating this determinant: \[ = \hat{i} \begin{vmatrix} 1 & -1 \\ 3 & 3 \end{vmatrix} - \hat{j} \begin{vmatrix} 1 & -1 \\ 2 & 3 \end{vmatrix} + \hat{k} \begin{vmatrix} 1 & 1 \\ 2 & 3 \end{vmatrix} \] Calculating each of these 2x2 determinants: 1. \(\begin{vmatrix} 1 & -1 \\ 3 & 3 \end{vmatrix} = (1)(3) - (-1)(3) = 3 + 3 = 6\) 2. \(\begin{vmatrix} 1 & -1 \\ 2 & 3 \end{vmatrix} = (1)(3) - (-1)(2) = 3 + 2 = 5\) 3. \(\begin{vmatrix} 1 & 1 \\ 2 & 3 \end{vmatrix} = (1)(3) - (1)(2) = 3 - 2 = 1\) Putting it all together: \[ \vec{b_1} \times \vec{b_2} = 6\hat{i} - 5\hat{j} + 1\hat{k} \] ### Step 3: Calculate the magnitude of \(\vec{b_1} \times \vec{b_2}\) \[ |\vec{b_1} \times \vec{b_2}| = \sqrt{6^2 + (-5)^2 + 1^2} = \sqrt{36 + 25 + 1} = \sqrt{62} \] ### Step 4: Calculate the dot product \((\vec{a_2} - \vec{a_1}) \cdot (\vec{b_1} \times \vec{b_2})\) \[ (\vec{a_2} - \vec{a_1}) \cdot (\vec{b_1} \times \vec{b_2}) = (\hat{i} - 12\hat{j} - 4\hat{k}) \cdot (6\hat{i} - 5\hat{j} + 1\hat{k}) \] Calculating this gives: \[ = (1)(6) + (-12)(-5) + (-4)(1) = 6 + 60 - 4 = 62 \] ### Step 5: Substitute into the distance formula \[ d = \frac{|62|}{\sqrt{62}} = \frac{62}{\sqrt{62}} = \sqrt{62} \] ### Final Answer The shortest distance between the two lines is: \[ d = \sqrt{62} \]
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Find the shortest distance between the lines : vec(r) = (4hat(i) - hat(j)) + lambda(hat(i) + 2hat(j) - 3hat(k)) and vec(r) = (hat(i) - hat(j) + 2hat(k)) + mu (2hat(i) + 4hat(j) - 5hat(k))

Show that the lines vec(r) =(hat(i) +2hat(j) +hat(k)) +lambda (hat(i)-hat(j)+hat(k)) " and " vec(r ) =(hat(i) +hat(j) -hat(k)) + mu (hat(i)- hat(j) + 2hat(k)) Do not intersect .

Find out whether the following pairs of lines are parallel, non parallel, & intersecting, or non-parallel & non-intersecting. vec(r_(1)) = hat(i) - hat(j) + 3hat(k) + lambda(hat(i) - hat(j)+hat(k)) vec(r_(2)) = hat(i) - hat(j) + 3hat(k) + lambda(hat(i) - hat(j) + hat(k)) vec(r_(2)) = 2hat(i) + 4hat(j) + 6hat(k) + mu (2hat(i) + hat(j) + 3hat(k))

Show that the lines vec( r) =(hat(i) +hat(j) -hat(k)) +lambda (3hat(i) -hat(j)) " and " vec( r) =(4hat(i) -hat(k)) + mu (2hat(i) +3hat(k)) intersect . Find the point of the intersection.

Find ( vec (a) xxvec (b)) and |vec(a) xx vec (b)| ,when (i) vec(a) = hat(i)-hat(j)+ 2hat(k) and vec(b)= 2 hat(i)+3 hat(j)-4hat(k) (ii) vec(a)= 2hat (i)+hat(j)+ 3hat(k) and vec(b)= 3hat(i)+5 hat(j) - 2 hat(k) (iii) vec(a)=hat(i)- 7 hat(j)+ 7hat(k) and vec(b) = 3 hat(i)-2hat(j)+2 hat(k) (iv) vec(a)= 4hat(i)+ hat(j)- 2hat(k) and vec(b) = 3 hat(i)+hat(k) (v) vec(a) = 3 hat(i) + 4 hat(j) and vec(b) = hat(i)+hat(j)+hat(k)

Find the angle between the vectors vec(a) and vec(b) , when (i) vec(a)=hat(i)-2hat(j)+3 hat(k) and vec(b)=3hat(i)-2hat(j)+hat(k) (ii) vec(a)=3 hat(i)+hat(j)+2hat(k) and vec(b)=2hat(i)-2hat(j)+4 hat(k) (iii) vec(a)=hat(i)-hat(j) and vec(b)=hat(j)+hat(k) .

RS AGGARWAL-STRAIGHT LINE IN SPACE-Exercise 27D
  1. Find the shortest distance between the given line vec(r )=(hat(i) +h...

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  2. vec(r )=(-4hat(i)+4hat(j) +hat(k)) + lambda (hat(i) +hat(j) -hat(k)) ...

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  3. vec(r ) =(hat(i) +2hat(j) +3hat(k)) + lambda(hat(i) -3hat(j) +2hat(k))...

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  4. Find the shortest distance between the given line vec(r )=(hat(i) +2h...

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  5. Find the shortest distance between the given line vec(r ) =(hat(i)+2h...

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  6. Find the shortest distance between the given line vec(r ) =(6hat(i) +...

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  7. Find the shortest distance between the given line vec(r) =(3-t) hat(i...

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  8. Find the shortest distance between the given line vec(r ) =(lambda-1)...

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  9. Compute the shortest distance between the lines vec(r )=(hat(i) ...

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  10. Show that the lines vec(r )=(3hat(i) -15hat(j) + 9hat(k)) + lambd...

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  11. Show that the lines vec( r)=(2hat(i) -3hat(k)) + lambda(hat(i) +2h...

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  12. Show that the lines vec(r )=(hat(i) +2hat(j) +3hat(k)) + lambda(2h...

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  13. Find the shortest distance between the lines vecr=(hati+2hatj-4hatk)+...

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  14. Find the distance between the parallel lines L(1) " and " L(2) w...

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  15. Find the vector equtions of a line passing through the point (2,...

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  16. Write the vector equations of each of the following lines and h...

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  17. Find the shortest distance between the lines (x-1)/2=(y-2)/3=(z-3)/...

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  18. Find the shortest distance distance between the following lines :(x-1)...

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  19. Find the shortest distance between the lines(x-12)/(-9) =(y-1)/(4)=(z-...

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