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Write the Value of ∣ ∣ ∣ a + I B C + I D − C + I D a − I B ∣ ∣ ∣ . - Mathematics

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प्रश्न

Write the value of  \[\begin{vmatrix}a + ib & c + id \\ - c + id & a - ib\end{vmatrix} .\]

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उत्तर

\[\begin{vmatrix}a + ib & c + id \\ - c + id & a - ib\end{vmatrix}\] 
\[ = a^2 - iab + iab - i^2 b^2 - ( - c^2 - icd + icd + i^2 d^2 )\] 
\[ = a^2 - i^2 b^2 + c^2 - i^2 d^2 \] 
Here,
\[ i^2 = - 1\] 
\[ \Rightarrow \begin{vmatrix}a + ib & c + id \\ - c + id & a - ib\end{vmatrix} = a^2 + b^2 + c^2 + d^2 \] 

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पाठ 6: Determinants - Exercise 6.6 [पृष्ठ ९१]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 6 Determinants
Exercise 6.6 | Q 34 | पृष्ठ ९१

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