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If |veca|=2, |vecb|=5 and |vecaxxvecb|=8...

If `|veca|=2, |vecb|=5 and |vecaxxvecb|=8` then find the value of `veca.vecb`

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`veca.vecb= |veca||vecb|costheta,but |vecaxxvecb|=|veca||vecb|sintheta`
` or sin theta (|veca xx vecb|)/(|veca||vecb|)= 4/5 Rightarrow 4/5 Rightarrow theta= 3/5`
thereforem , `veca.vecb= 2xx5xx 3/5 = 6`
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CENGAGE-DIFFERENT PRODUCTS OF VECTORS AND THEIR GEOMETRICAL APPLICATIONS -Exercise
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  2. If veca=2hati+ 3hatj-5hatk,vecb =m hati+nhatj +12 hatk and veca xx vec...

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  3. If |veca|=2, |vecb|=5 and |vecaxxvecb|=8 then find the value of veca.v...

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  4. If veca xx vecb = vecb xx vecc ne 0 where veca , vecb and vecc are co...

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  5. If veca = 2vecj+3vecj-veck, vecb =-veci+2vecj-4veck and vecc=veci + ve...

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  6. if the vectors vecc, veca = xhati +yhatj + zhatk and vecb = hatj are s...

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  7. given that veca. vecb = veca.vecc, veca xx vecb= veca xx vecc and veca...

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  8. Show that (veca-vecb)xx(veca+vecb)=2(vecaxxvecb)

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  9. If vec x and vecy are unit vectors and |vecz| = 2/sqrt7 such that vecz...

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  10. prove that (veca.hati)(vecaxxhati)+(veca.hatj)(vecaxxhatj)+(veca.hatk)...

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  11. If vec a, vec b, vec c are unit vectors such that vec a+ vec b+ vec c ...

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  12. A particle has an angular speed of 3 rad/s and the axis of rotation...

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  13. If veca,vecb,vecc be unit vectors such that veca.vecb=veca.vecc=0 and ...

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  14. if (vecaxxvecb)^(2)+ (veca.vecb)^(2) = 144 and |veca|=4 the find the v...

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  15. Given |veca|=|vecb|=1 and |veca + vecb|= sqrt3 "if" vecc is a vector s...

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  16. Find the moment of vec F about point (2, -1, 3), where force vec ...

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  17. If veca , vecb , vecc and vecd are four non-coplanar unit vectors such...

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  18. If vectors veca, vecb and vecc are coplanar, show that |{:(veca, vecb,...

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  19. If the volume of a parallelepiped whose adjacent edges are vec a=2...

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  20. If veca=hati+hatj+hatk and vecb = hati-2hatj+hatk then find vector vec...

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