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Given that veca,vecb,vecp,vecq are four...

Given that `veca,vecb,vecp,vecq` are four vectors such that `veca + vecb= mu vecp, vecb.vecq=0 and |vecb|^(2) = 1 ` where `mu` is a sclar. Then `|(veca.vecq) vecp-(vecp.vecq)veca|` is equal to

(a)`2|vecpvecq|` (b)`(1//2)|vecp.vecq|` (c)`|vecpxxvecq|` (d)`|vecp.vecq|`

A

`2|vecpvecq|`

B

`(1//2)|vecp.vecq|`

C

`|vecpxxvecq|`

D

`|vecp.vecq|`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of \( |(\vec{a} \cdot \vec{q}) \vec{p} - (\vec{p} \cdot \vec{q}) \vec{a}| \) given the conditions on the vectors. Let's break it down step by step. ### Step 1: Start with the given equations We have the following equations: 1. \( \vec{a} + \vec{b} = \mu \vec{p} \) 2. \( \vec{b} \cdot \vec{q} = 0 \) 3. \( |\vec{b}|^2 = 1 \) ### Step 2: Take the dot product with \( \vec{q} \) Taking the dot product of the first equation with \( \vec{q} \): \[ \vec{a} \cdot \vec{q} + \vec{b} \cdot \vec{q} = \mu (\vec{p} \cdot \vec{q}) \] Since \( \vec{b} \cdot \vec{q} = 0 \), we can simplify this to: \[ \vec{a} \cdot \vec{q} = \mu (\vec{p} \cdot \vec{q}) \] ### Step 3: Express \( \vec{b} \) in terms of \( \vec{a} \) and \( \vec{p} \) From the first equation, we can express \( \vec{b} \) as: \[ \vec{b} = \mu \vec{p} - \vec{a} \] ### Step 4: Substitute \( \vec{b} \) into the expression Now we need to evaluate the expression \( |(\vec{a} \cdot \vec{q}) \vec{p} - (\vec{p} \cdot \vec{q}) \vec{a}| \): Substituting \( \vec{a} \cdot \vec{q} = \mu (\vec{p} \cdot \vec{q}) \): \[ |(\mu (\vec{p} \cdot \vec{q})) \vec{p} - (\vec{p} \cdot \vec{q}) \vec{a}| \] ### Step 5: Factor out \( \vec{p} \cdot \vec{q} \) Factoring out \( \vec{p} \cdot \vec{q} \): \[ |(\vec{p} \cdot \vec{q}) (\mu \vec{p} - \vec{a})| \] ### Step 6: Use the magnitude of \( \vec{b} \) From the third equation, we know \( |\vec{b}|^2 = 1 \), hence \( |\vec{b}| = 1 \): \[ |\mu \vec{p} - \vec{a}| = |\vec{b}| \] Thus, we have: \[ |\mu \vec{p} - \vec{a}| = 1 \] ### Step 7: Final expression Now substituting back, we find: \[ |(\vec{p} \cdot \vec{q})| \cdot 1 = |\vec{p} \cdot \vec{q}| \] ### Conclusion Thus, the final result is: \[ |(\vec{a} \cdot \vec{q}) \vec{p} - (\vec{p} \cdot \vec{q}) \vec{a}| = |\vec{p} \cdot \vec{q}| \] The answer is option **(d)** \( |\vec{p} \cdot \vec{q}| \). ---

To solve the problem, we need to find the value of \( |(\vec{a} \cdot \vec{q}) \vec{p} - (\vec{p} \cdot \vec{q}) \vec{a}| \) given the conditions on the vectors. Let's break it down step by step. ### Step 1: Start with the given equations We have the following equations: 1. \( \vec{a} + \vec{b} = \mu \vec{p} \) 2. \( \vec{b} \cdot \vec{q} = 0 \) 3. \( |\vec{b}|^2 = 1 \) ...
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CENGAGE ENGLISH-DIFFERENT PRODUCTS OF VECTORS AND THEIR GEOMETRICAL APPLICATIONS -Exercises MCQ
  1. If vecr and vecs are non-zero constant vectors and the scalar b is cho...

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  2. veca and vecb are two unit vectors that are mutually perpendicular. A...

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  3. Given that veca,vecb,vecp,vecq are four vectors such that veca + vecb...

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  4. The position vectors of the vertices A, B and C of a triangle are thre...

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  5. If a is real constant A ,Ba n dC are variable angles and sqrt(a^2-4)ta...

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  6. The vertex A triangle A B C is on the line vec r= hat i+ hat j+lambda...

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  7. A non-zero vecto veca is such tha its projections along vectors (hati ...

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  8. Position vector hatk is rotated about the origin by angle 135^(@) in ...

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  9. In a quadrilateral A B C D , vec A C is the bisector of vec A Ba n d ...

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  10. In AB, DE and GF are parallel to each other and AD, BG and EF ar para...

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  11. Vectors hata in the plane of vecb = 2 hati +hatj and vecc = hati-hatj ...

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  12. Let A B C D be a tetrahedron such that the edges A B ,A Ca n dA D ar...

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  13. Let vecf(t)=[t] hat i+(t-[t]) hat j+[t+1] hat k , w h e r e[dot] deno...

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  14. If veca is parallel to vecb xx vecc, then (veca xx vecb) .(veca xx vec...

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  15. The three vectors hat i+hat j,hat j+hat k, hat k+hat i taken two at a ...

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  16. If vecd=vecaxxvecb+vecbxxvecc+vecc+veccxxveca is a non- zero vector an...

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  17. If |veca|=2 and |vecb|=3 and veca.vecb=0, " then " (vecaxx(vecaxx(veca...

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  18. If two diagonals of one of its faces are 6hati + 6 hatk and 4 hatj + ...

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  19. The volume of a tetrahedron fomed by the coterminus edges veca , vecb ...

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  20. If veca ,vecb and vecc are three mutually orthogonal unit vectors , th...

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