A vector vector i has magnitude 14 and direction ratios 2, 3, –6. Find the direction cosines and components of vector i, given that vector i makes an acute angle with x-axis.

Given that,

Magnitude of vector = 14



Also, direction ratios = 2 : 3 : -6





Also can be defined as,



Know that, the direction cosines of a vector are the cosines of the angles between the vector and the three coordinate axes.


, the direction cosines l, m and n are



[ ]




[ ]



[ ]



And we know that,


l2 + m2 + n2 = 1






49k2 = 196



k2 = 4


k = ±√4


k = ±2


Since, makes an acute angle with x-axis, then k will be positive.


k = 2


The direction cosines are





The components of can be found out by,







Thus, the direction cosines (l, m, n) are ; and the components of are .


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