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If  a=7i+j-4k and b=2i+6j+3k , then find the projection of  a and b - Mathematics

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Question

If `vec a=7hati+hatj-4hatk and vecb=2hati+6hatj+3hatk` , then find the projection of `vec a and vecb`

Solution

`vec a=7hati+hatj-4hatk`

` vecb=2hati+6hatj+3hatk,`

The projection of ` veca ` and `vecb`is given by

`1/|b'|(veca.vecb)=((7xx2)+(1xx6)+(-4xx3))/(sqrt(2^2+6^2+3^2))=8/7`

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2014-2015 (March) Delhi Set 1

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