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If veca, vecb, vecc are unit vectors suc...

If `veca, vecb, vecc` are unit vectors such that `veca. vecb=0, (veca-vecc).(vecb+vecc)=0` and `vecc=lambdaveca+muvecb+omega(veca xx vecb)`, where `lambda, mu, omega` are scalars, then

A

`mu^(2)+omega^(2)=1`

B

`lambda+mu=1`

C

`(mu+1)^(2)+mu^(2)+omega^(2)=1`

D

`lambda^(2)+mu^(2)=1`

Text Solution

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To solve the given problem step by step, we will analyze the conditions provided and derive the necessary relationships among the vectors. ### Step 1: Understand the Given Conditions We are given three unit vectors \( \vec{a}, \vec{b}, \vec{c} \) such that: 1. \( \vec{a} \cdot \vec{b} = 0 \) (indicating that \( \vec{a} \) and \( \vec{b} \) are perpendicular). 2. \( (\vec{a} - \vec{c}) \cdot (\vec{b} + \vec{c}) = 0 \). 3. \( \vec{c} = \lambda \vec{a} + \mu \vec{b} + \omega (\vec{a} \times \vec{b}) \), where \( \lambda, \mu, \omega \) are scalars. ### Step 2: Expand the Second Condition We start with the second condition: \[ (\vec{a} - \vec{c}) \cdot (\vec{b} + \vec{c}) = 0 \] Expanding this, we have: \[ \vec{a} \cdot \vec{b} + \vec{a} \cdot \vec{c} - \vec{c} \cdot \vec{b} - \vec{c} \cdot \vec{c} = 0 \] Since \( \vec{a} \cdot \vec{b} = 0 \), this simplifies to: \[ \vec{a} \cdot \vec{c} - \vec{c} \cdot \vec{b} - \vec{c} \cdot \vec{c} = 0 \] ### Step 3: Substitute \( \vec{c} \) Substituting \( \vec{c} = \lambda \vec{a} + \mu \vec{b} + \omega (\vec{a} \times \vec{b}) \) into the equation: \[ \vec{a} \cdot (\lambda \vec{a} + \mu \vec{b} + \omega (\vec{a} \times \vec{b})) - (\lambda \vec{a} + \mu \vec{b} + \omega (\vec{a} \times \vec{b})) \cdot \vec{b} - \|\vec{c}\|^2 = 0 \] ### Step 4: Calculate Each Dot Product 1. \( \vec{a} \cdot \vec{c} = \lambda \|\vec{a}\|^2 + \mu (\vec{a} \cdot \vec{b}) + \omega (\vec{a} \cdot (\vec{a} \times \vec{b})) = \lambda \) (since \( \|\vec{a}\|^2 = 1 \) and the other two terms are zero). 2. \( \vec{c} \cdot \vec{b} = \lambda (\vec{a} \cdot \vec{b}) + \mu \|\vec{b}\|^2 + \omega ((\vec{a} \times \vec{b}) \cdot \vec{b}) = \mu \) (since \( \|\vec{b}\|^2 = 1 \) and the other two terms are zero). 3. \( \|\vec{c}\|^2 = \lambda^2 + \mu^2 + \omega^2 \) (since \( \vec{c} \) is a unit vector). ### Step 5: Substitute Back into the Equation Now substituting back, we get: \[ \lambda - \mu - (\lambda^2 + \mu^2 + \omega^2) = 0 \] Rearranging gives: \[ \lambda - \mu = \lambda^2 + \mu^2 + \omega^2 \] ### Step 6: Analyzing the Magnitude Since \( \vec{c} \) is a unit vector, we have: \[ \lambda^2 + \mu^2 + \omega^2 = 1 \] ### Step 7: Solve for Relationships From \( \lambda - \mu = \lambda^2 + \mu^2 + \omega^2 \) and \( \lambda^2 + \mu^2 + \omega^2 = 1 \), we can conclude: \[ \lambda - \mu = 1 \] This implies: \[ \lambda = \mu + 1 \] ### Conclusion Thus, we have established the relationships among \( \lambda, \mu, \) and \( \omega \) based on the conditions given in the problem.

To solve the given problem step by step, we will analyze the conditions provided and derive the necessary relationships among the vectors. ### Step 1: Understand the Given Conditions We are given three unit vectors \( \vec{a}, \vec{b}, \vec{c} \) such that: 1. \( \vec{a} \cdot \vec{b} = 0 \) (indicating that \( \vec{a} \) and \( \vec{b} \) are perpendicular). 2. \( (\vec{a} - \vec{c}) \cdot (\vec{b} + \vec{c}) = 0 \). 3. \( \vec{c} = \lambda \vec{a} + \mu \vec{b} + \omega (\vec{a} \times \vec{b}) \), where \( \lambda, \mu, \omega \) are scalars. ...
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