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Tamil Nadu Board of Secondary EducationHSC Science Class 11

Find the direction cosines and direction ratios for the following vector ijk5i^-3j^-48k^

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Question

Find the direction cosines and direction ratios for the following vector

`5hat"i" - 3hat"j" - 48hat"k"`

Sum
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Solution

The direction ratios of the vector `5hat"i" - 3hat"j" - 48hat"k"` are (5, – 3, – 48)

The direction cosines of the vector `5hat"i" - 3hat"j" - 48hat"k"` are

`5/sqrt(5^2 + (-3)^2 + (-48)^2), (-3)/sqrt(5^2 + (-3)^2 + (-48)^2), (-48)/sqrt(5^2 + (-3)^2 + (-48)^2)`

`5/sqrt(25 + 9 + 2304), (-3)/sqrt(25 + 9 + 2304), (-48)/sqrt(25 + 9 + 2304)`

`(5/sqrt(2338), (-3)/sqrt(2338), (-4)/sqrt(2338))`

Direction ratios = (5, – 3, – 48)

Direction cosies = `(5/sqrt(2338), (-3)/sqrt(2338), (-4)/sqrt(2338))`

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Chapter 8: Vector Algebra - Exercise 8.2 [Page 68]

APPEARS IN

Samacheer Kalvi Mathematics - Volume 1 and 2 [English] Class 11 TN Board
Chapter 8 Vector Algebra
Exercise 8.2 | Q 3. (iv) | Page 68

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