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If aijkbijkcijka→=i^-2j^+3k^,b→=2i^+j^-2k^,c→=3i^+2j^+k^, find abca→⋅(b→×c→) - Mathematics

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प्रश्न

If `vec"a" = hat"i" - 2hat"j" + 3hat"k", vec"b" = 2hat"i" + hat"j" - 2hat"k", vec"c" = 3hat"i" + 2hat"j" + hat"k"`, find `vec"a" * (vec"b" xx vec"c")`

योग

उत्तर

Given `vec"a" = hat"i" - 2hat"j" + 3hat"k"` 

`vec"b" = 2hat"i" + hat"j" - 2hat"k"`

`vec"c" = 3hat"i" + 2hat"j" + hat"k"`

`vec"b" xx vec"c" = |(vec"i", vec"j", vec"k"),(2, 1, -2),(3, 2, 1)|`

`vec"b" xx vec"c" = 5hat"i" - 8hat"j" + hat"k"`

`vec"a"*(vec"b" xx vec"c")` = 5 + 16 + 3 = 24

Aliter: `vec"a"*(vec"b" xx vec"c") = [vec"a"  vec"b"  vec"c"]`

= `|(1, -2, 3),(2, 1, -2),(3, 2, 1)|`

= 1(5) + 2(8) + 3(1)

= 4 + 16 + 3

= 24

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 6: Applications of Vector Algebra - Exercise 6.2 [पृष्ठ २३७]

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सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 12 TN Board
अध्याय 6 Applications of Vector Algebra
Exercise 6.2 | Q 1 | पृष्ठ २३७

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