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In any triangle A B C , prove the projec...

In any triangle `A B C ,` prove the projection formula`a=b cosC+c cosB` using vector method.

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CENGAGE PUBLICATION-VECTOR ALGEBRA-All Questions
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  2. If a+2b+3c=4, then find the least value (to the nearest integer) of ...

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  3. In any triangle A B C , prove the projection formulaa=b cosC+c cosB ...

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  4. Prove that an angle inscribed in a semi-circle is a right angle usi...

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  6. Prove by vector method that cos(A+B)=cos AcosB-sinAsinBdot

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  7. If the scalar projection of vector x hat i- hat j+ hat k on vector 2...

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  8. If vec a=x hat i+(x-1) hat j+ hat k and vec b=(x+1) hat i+ hat j+a ha...

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  9. A unit vector a makes an angle pi/ 4 with z-axis. If a + i + j is a un...

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  10. if veca, vecb and vecc are there mutually perpendicular unit vectors a...

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  11. If vec a , vec b , and vec c be non-zero vectors such that no two ...

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  12. If vec p , vec q , vec r denote vector vec bxx vec c , vec cxx vec a...

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  13. If vec a and vec b be two non-collinear unit vector such that vec ...

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  14. Show that ( vec a- vec b)xx( vec a+ vec b)=2( vec axx vec b)dot

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  15. Prove that ( vec a.( vec bxx hat i)) hat i+( vec a.( vec bxx hat j)) h...

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  16. For any four vectors, vec a , vec b , vec c and vec d prove that vec...

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  17. If vec a , vec b, and vec c are three vectors such that vec axx ve...

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  18. If vec a= vec p+ vec q , vec pxx vec b=0a n d vec qdot vec b=0, then ...

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  19. If vec a= hat i+ hat j+ hat k and vec b= hat i-2 hat j+ hat k , then ...

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  20. If non-zero vectors veca and vecb are perpendicular to each ot...

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