मराठी

The vector in the direction of the vector ijki^-2j^+2k^ that has magnitude 9 is ______. - Mathematics

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प्रश्न

The vector in the direction of the vector `hat"i" - 2hat"j" + 2hat"k"` that has magnitude 9 is ______.

पर्याय

  • `hat"i" - 2hat"j" + 2hat"k"`

  • `(hat"i" - 2hat"j" + 2hat"k")/3`

  • `3(hat"i" - 2hat"j" + 2hat"k")`

  • `9(hat"i" - 2hat"j" + 2hat"k")`

MCQ
रिकाम्या जागा भरा
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उत्तर

The vector in the direction of the vector `hat"i" - 2hat"j" + 2hat"k"` that has magnitude 9 is `3(hat"i" - 2hat"j" + 2hat"k")`.

Explanation:

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

Unit vector in the direction of `vec"a" = vec"a"/|vec"a"|`

= `(hat"i" - 2hat"j" + 2hat"k")/sqrt((1)^2 + (-2)^2 + (2)^2)`

= `(hat"i" - 2hat"j" + 2hat"k")/sqrt(1 + 4 + 4)`

= `(hat"i" - 2hat"j" + 2hat"k")/3`

∴ Vector of magnitude 9 = `(9(hat"i" - 2hat"j" + 2hat"k"))/3`

= `(3hat"i" - 2hat"j" + 2hat"k")`

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Magnitude and Direction of a Vector
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पाठ 10: Vector Algebra - Exercise [पृष्ठ २१६]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
पाठ 10 Vector Algebra
Exercise | Q 19 | पृष्ठ २१६

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