Questions
Question 1
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Compute \(3(2,-5)\).
Question 2
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Compute \(-2(4\mathbf i-\mathbf j)\).
Question 3
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A vector \(\mathbf v=(3,4)\) is doubled. Find \(2\mathbf v\) and its magnitude.
Question 4
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Find \(\frac12(8,-6,10)\).
Question 5
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A displacement \((5,0)\) m is multiplied by \(-1\). Interpret the result.
Question 6
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Find \(k\) if \(k(2,3)=(10,15)\).
Question 7
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Calculate \(-3(1,-2,4)+2(0,5,-1)\).
Question 8
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A force \(\mathbf F=(4,-3)\) N is increased by a factor of \(2.5\). Find the new vector.
Question 9
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Find the unit vector in the direction of \(\mathbf a=(6,8)\).
Question 10
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Find a vector parallel to \((2,-1,2)\) with magnitude \(9\) and the same direction.
Question 11
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Determine whether \((12,-8)\) is a scalar multiple of \((-3,2)\).
Question 12
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Find \(a\) and \(b\) if \(4(a,b)=(-12,20)\).
Question 13
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For \(\mathbf u=(1,2)\) and \(\mathbf v=(-3,4)\), compute \(5\mathbf u-2\mathbf v\).
Question 14
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A velocity \((9,12)\) m s\(^{-1}\) is scaled to one third of its magnitude in the opposite direction. Find it.
Question 15
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Find \(t\) such that \(t(4,-2)\) has magnitude \(10\).
Question 16
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Verify \(2(\mathbf a+\mathbf b)=2\mathbf a+2\mathbf b\) for \(\mathbf a=(1,-3)\), \(\mathbf b=(4,5)\).
Question 17
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Find \(k\) so that \(k(3,4)\) has \(y\)-component \(-12\), then give the vector.
Question 18
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A line uses direction vector \(\mathbf b=(2,-1,3)\). Give two non-zero scalar multiples for the same line direction, then explain which one reverses the parameter direction.
Question 19
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Solve \(3(2x,1-x)=(12,-3)\), then decide whether \((2x,1-x)\) points in the same direction as \((12,-3)\).
Question 20
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A vector \(\mathbf a=(2,-2,1)\) is multiplied successively by \(k\) and \(m\), giving \((-18,18,-9)\). Find \(km\), and describe the effect on direction and length.