Write the Direction Cosines of the Vector ^ I + 2 ^ J + 3 ^ K . - Mathematics

Question

Write the direction cosines of the vector $\hat{i} + 2 \hat{j} + 3 \hat{k}$ .

Solution

Given: $\hat{i} + 2 \hat{j} + 3 \hat{k}$
Then, direction cosines are $\frac{1}{\sqrt{1^{2} + 2^{2} + 3^{2}}}, \frac{2}{\sqrt{1^{2} + 2^{2} + 3^{2}}}, \frac{3}{\sqrt{1^{2} + 2^{2} + 3^{2}}}$ or, $\frac{1}{\sqrt{14}}, \frac{2}{\sqrt{14}}, \frac{3}{\sqrt{14}}$ .

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Direction Cosines

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Q 38 Q 37 Q 39

Chapter 23: Algebra of Vectors - Very Short Answers [Page 76]

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RD Sharma Mathematics [English] Class 12

Chapter 23 Algebra of Vectors
Very Short Answers | Q 38 | Page 76

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Write the Direction Cosines of the Vector ^ I + 2 ^ J + 3 ^ K . - Mathematics

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