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vecp=3hati+2hatj+hatk ,vecq=2hati+hatj+h...

`vecp=3hati+2hatj+hatk ,vecq=2hati+hatj+hatk, vecr` is `bot` to both `vecp+vecq and (vecp-vecq), absvecr=sqrt3. vecr=ahati+bhatj+chatk.` then find `absveca + absvecb + absvecc`.

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To solve the problem step by step, we start with the given vectors and the conditions provided. ### Step 1: Define the vectors We are given: \[ \vec{p} = 3\hat{i} + 2\hat{j} + \hat{k} \] \[ \vec{q} = 2\hat{i} + \hat{j} + \hat{k} \] ### Step 2: Calculate \(\vec{p} + \vec{q}\) and \(\vec{p} - \vec{q}\) First, we find: \[ \vec{p} + \vec{q} = (3 + 2)\hat{i} + (2 + 1)\hat{j} + (1 + 1)\hat{k} = 5\hat{i} + 3\hat{j} + 2\hat{k} \] \[ \vec{p} - \vec{q} = (3 - 2)\hat{i} + (2 - 1)\hat{j} + (1 - 1)\hat{k} = 1\hat{i} + 1\hat{j} + 0\hat{k} \] ### Step 3: Find the cross product \((\vec{p} + \vec{q}) \times (\vec{p} - \vec{q})\) We need to compute the cross product: \[ \vec{a} = \vec{p} + \vec{q} = 5\hat{i} + 3\hat{j} + 2\hat{k} \] \[ \vec{b} = \vec{p} - \vec{q} = 1\hat{i} + 1\hat{j} + 0\hat{k} \] The cross product \(\vec{a} \times \vec{b}\) is given by the determinant: \[ \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ 5 & 3 & 2 \\ 1 & 1 & 0 \end{vmatrix} \] Calculating this determinant: \[ \hat{i} \begin{vmatrix} 3 & 2 \\ 1 & 0 \end{vmatrix} - \hat{j} \begin{vmatrix} 5 & 2 \\ 1 & 0 \end{vmatrix} + \hat{k} \begin{vmatrix} 5 & 3 \\ 1 & 1 \end{vmatrix} \] Calculating each of the 2x2 determinants: 1. \(\begin{vmatrix} 3 & 2 \\ 1 & 0 \end{vmatrix} = (3 \cdot 0 - 2 \cdot 1) = -2\) 2. \(\begin{vmatrix} 5 & 2 \\ 1 & 0 \end{vmatrix} = (5 \cdot 0 - 2 \cdot 1) = -2\) 3. \(\begin{vmatrix} 5 & 3 \\ 1 & 1 \end{vmatrix} = (5 \cdot 1 - 3 \cdot 1) = 2\) Thus, we have: \[ \vec{a} \times \vec{b} = -2\hat{i} + 2\hat{j} + 2\hat{k} \] ### Step 4: Express \(\vec{r}\) in terms of \(\lambda\) Since \(\vec{r}\) is perpendicular to both \(\vec{a}\) and \(\vec{b}\), we can express \(\vec{r}\) as: \[ \vec{r} = \lambda (-2\hat{i} + 2\hat{j} + 2\hat{k}) \] This means: \[ \vec{r} = -2\lambda \hat{i} + 2\lambda \hat{j} + 2\lambda \hat{k} \] ### Step 5: Find the magnitude of \(\vec{r}\) The magnitude of \(\vec{r}\) is given as: \[ |\vec{r}| = \sqrt{(-2\lambda)^2 + (2\lambda)^2 + (2\lambda)^2} = \sqrt{4\lambda^2 + 4\lambda^2 + 4\lambda^2} = \sqrt{12\lambda^2} = 2\sqrt{3}|\lambda| \] We know that \(|\vec{r}| = \sqrt{3}\), hence: \[ 2\sqrt{3}|\lambda| = \sqrt{3} \] This gives: \[ |\lambda| = \frac{1}{2} \] ### Step 6: Substitute \(\lambda\) back into \(\vec{r}\) Now substituting \(\lambda\) back into \(\vec{r}\): \[ \vec{r} = -2\left(\frac{1}{2}\right)\hat{i} + 2\left(\frac{1}{2}\right)\hat{j} + 2\left(\frac{1}{2}\right)\hat{k} = -\hat{i} + \hat{j} + \hat{k} \] ### Step 7: Identify components \(a\), \(b\), and \(c\) From \(\vec{r} = a\hat{i} + b\hat{j} + c\hat{k}\), we have: \[ a = -1, \quad b = 1, \quad c = 1 \] ### Step 8: Calculate the absolute values and their sum Now we calculate: \[ |\vec{a}| + |\vec{b}| + |\vec{c}| = | -1 | + | 1 | + | 1 | = 1 + 1 + 1 = 3 \] ### Final Answer Thus, the final answer is: \[ \boxed{3} \]
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