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If $\left(\dfrac{1}{2},\,\dfrac{1}{3},\,n\right)$ are the direction cosines of a line, then the value of $n$ is
If $\left(\dfrac{1}{2},\,\dfrac{1}{3},\,n\right)$ are the direction cosines of a line, then the value of $n$ is
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Direction cosines $(l, m, n)$ always satisfy $l^2 + m^2 + n^2 = 1$. Use this to find any unknown direction cosine.
Updated On: Apr 8, 2026
- $\dfrac{\sqrt{23}}{6}$
- $\dfrac{23}{36}$
- $\dfrac{2}{3}$
- $\dfrac{2}{3}$
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The Correct Option is A
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