Questions
Question 1
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Write a vector equation for the line through \((1,2)\) with direction \((3,-1)\).
Question 2
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Find the point on \(\mathbf r=(1,2)+\lambda(3,-1)\) when \(\lambda=2\).
Question 3
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Does \((7,0)\) lie on \(\mathbf r=(1,2)+\lambda(3,-1)\)?
Question 4
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Find a direction vector for the line through \(A=(1,4,0)\) and \(B=(3,1,5)\).
Question 5
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Write a line through \(A=(1,4,0)\) and \(B=(3,1,5)\).
Question 6
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Find where \(\mathbf r=(2,1)+t(1,3)\) meets the \(y\)-axis.
Question 7
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Find where \(\mathbf r=(2,1)+t(1,3)\) meets the line \(y=7\).
Question 8
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Are lines \(\mathbf r=(0,1)+s(2,4)\) and \(\mathbf r=(3,-1)+t(1,2)\) parallel?
Question 9
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Find the intersection of \((0,0)+s(1,2)\) and \((3,0)+t(-1,1)\).
Question 10
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Find the distance from \(C=(1,2,3)\) to the line \(\mathbf r=(0,0,0)+\lambda(2,0,1)\).
Question 11
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Find a line through \((1,1,1)\) parallel to \((2,-1,0)\).
Question 12
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Find \(t\) if \((5,-1,1)\) lies on \(\mathbf r=(1,1,1)+t(2,-1,0)\).
Question 13
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Find the closest point on \(\mathbf r=(0,0)+t(1,0)\) to \(C=(3,4)\).
Question 14
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Write symmetric equations for \(\mathbf r=(1,2,3)+t(2,-1,4)\).
Question 15
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Find the angle between lines with directions \((1,0,1)\) and \((0,1,1)\).
Question 16
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Do \(\mathbf r=(1,0,0)+s(1,1,0)\) and \(\mathbf r=(0,1,1)+t(1,1,0)\) represent the same line?
Question 17
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Find a parameter value where \(\mathbf r=(2,3,4)+t(1,-1,2)\) has \(z=10\).
Question 18
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Find the line through \((2,0,-1)\) parallel to \((1,-1,2)\), and show that this line is parallel to the plane with normal \((1,1,0)\).
Question 19
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Decide whether \((4,6)\) lies on the segment from \((1,0)\) to \((5,8)\), then find the ratio in which it divides the segment.
Question 20
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Find the shortest distance between the parallel lines \(\ell_1:(0,0)+s(1,0)\) and \(\ell_2:(0,3)+t(1,0)\), and identify one pair of closest points.