मराठी

If the direction ratios of a line are 1, 1, 2, find the direction cosines of the line.

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प्रश्न

If the direction ratios of a line are 1, 1, 2, find the direction cosines of the line.

बेरीज
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उत्तर

The direction cosines are given by

l = `"a"/sqrt("a"^2 + "b"^2 + "c"^2)`

m = `"b"/sqrt("a"^2 + "b"^2 + "c"^2)`

n = `"c"/sqrt("a"^2 + "b"^2 + "c"62)`

Here a, b, c are 1, 1, 2, respectively

Therefore, l = `1/sqrt(1^2 + 1^2 + 2^2)`

m = `1/sqrt(1^2 + 1^2 + 2^2)`

n = `"c"/sqrt(1^2 + 1^2 + 2^2)`

i.e., l = `1/sqrt(6)`

m = `1/sqrt(6)`

n = `2/sqrt(6)`

i.e. `+-(1/sqrt(6), 1/sqrt(6), 2/sqrt(6))` are D.C’s of the line.

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पाठ 11: Three Dimensional Geometry - Solved Examples [पृष्ठ २२४]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
पाठ 11 Three Dimensional Geometry
Solved Examples | Q 1 | पृष्ठ २२४

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