Questions
Question 1
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Compute \((1,0,0)\times(0,1,0)\).
Question 2
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Compute \((0,1,0)\times(1,0,0)\).
Question 3
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Find \((2,3,4)\times(1,0,2)\).
Question 4
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Find the area of the parallelogram spanned by \((3,0,0)\) and \((0,4,0)\).
Question 5
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Find the area of the triangle with sides \((2,0,0)\) and \((0,5,0)\) from one vertex.
Question 6
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Compute the torque \(\boldsymbol\tau=\mathbf r\times\mathbf F\) for \(\mathbf r=(2,0,0)\) m and \(\mathbf F=(0,3,0)\) N.
Question 7
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Test whether \((1,2,3)\) and \((2,4,6)\) are parallel using a cross product.
Question 8
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Find a vector perpendicular to \((1,1,0)\) and \((0,1,1)\).
Question 9
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Compute \((3,-1,2)\times(2,1,0)\).
Question 10
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Find \(|(1,2,2)\times(2,0,1)|\).
Question 11
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Find the unit normal to the plane spanned by \((1,0,1)\) and \((0,2,0)\).
Question 12
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Compute \((\mathbf i+\mathbf j)\times(\mathbf j+\mathbf k)\).
Question 13
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Find \(k\) if \((1,2,3)\times(k,4,6)=\mathbf0\).
Question 14
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Find the orientation sign of \((1,0,0)\times(0,1,0)\cdot(0,0,1)\).
Question 15
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A triangular plate has vertices \(A=(1,0,2)\), \(B=(2,2,2)\), and \(C=(4,0,-1)\). Find its area and a unit normal vector.
Question 16
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Compute \((2,-1,1)\times(1,3,-2)\).
Question 17
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Show that \((2,-1,1)\times(1,3,-2)\) is perpendicular to \((2,-1,1)\).
Question 18
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Find the sine of the angle between \((1,0,1)\) and \((0,1,1)\), then use it to find the area of the parallelogram they span.
Question 19
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For the triangle with vertices \(A=(0,0,0)\), \(B=(1,2,0)\), and \(C=(0,1,3)\), find a normal vector and decide which side of the triangle the point \(P=(6,-3,1)\) lies on relative to that normal.
Question 20
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A force \((0,5,0)\) N is applied at \((2,0,1)\) m. Find the torque about the origin, its magnitude, and explain whether the torque is perpendicular to the force.