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Find equation of line in vector form passing through the point (−1, 3, 5) and parallel to line \(\cfrac{x-3}2\) = \(\cfrac{y-3}3\) = z - 2. |
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Answer» Given that line passing through the point (−1, 3, 5) and parallel to line \(\cfrac{x-3}2\) = \(\cfrac{y-3}3\) =\(\cfrac{z-2}1\). Now, position vector of point (−1, 3, 5) is \(\vec a=-\hat i+3\hat j+5\hat k \). And direction ratios of given line \(\cfrac{x-3}2\) = \(\cfrac{y-3}3\) =\(\cfrac{z-2}1\). are 2, 3 and 1. Now, equation of line parallel to given line is \(\vec b=2\hat i+3\hat j+\hat k \). We know that vector form of line passing through the point p and parallel to vector \(\vec b\) is given by \(\vec r=\vec a+\lambda\vec b\) where \(\vec a\) is position vector of point p. Therefore, the vector equation of line passing through the point (−1, 3, 5) and parallel to vector \(\vec b\) is \(\vec r=\vec a+\lambda\vec b\) = \((-\hat i+3\hat j+5\hat k) \) + \(\lambda(2\hat i+3\hat j+\hat k) \). (Because \(\vec b\) is parallel to given line and we want to find the line parallel to given line. Therefore, required line is parallel to \(\vec b\). ) Hence, the vector equation of required line is \(\vec r=\) \((-\hat i+3\hat j+5\hat k) \) + \(\lambda(2\hat i+3\hat j+\hat k) \). |
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