मराठी

If Z 1 = 2 − I , Z 2 = − 2 + I , Find Re ( Z 1 Z 2 Z 1 ) - Mathematics

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प्रश्न

If \[z_1 = 2 - i, z_2 = - 2 + i,\] find 

Re \[\left( \frac{z_1 z_2}{z_1} \right)\]

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उत्तर

\[ z_1 = 2 - i, z_2 = - 2 + i, z_1 = 2 + i\]

\[ \therefore \left( \frac{z_1 z_2}{z_1} \right) = \left( \frac{\left[ 2 - i \right]\left[ - 2 + i \right]}{2 + i} \right)\]

\[ = \left( \frac{- 4 + 2i + 2i - i^2}{2 + i} \right)\]

\[ = \left( \frac{- 3 + 4i}{2 + i} \right)\]

\[ = \left[ \frac{- 3 + 4i}{2 + i} \times \left( \frac{2 - i}{2 - i} \right) \right]\]

\[ = \left( \frac{- 6 + 3i + 8i - 4 i^2}{2^2 - i^2} \right)\]

\[ = \left( \frac{- 2 + 11i}{4 - \left( - 1 \right)} \right)\]

\[ = \left( \frac{- 2 + 11i}{5} \right)\]

\[Re\left( \frac{z_1 z_2}{z_1} \right) = \frac{- 2}{5}\]

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पाठ 13: Complex Numbers - Exercise 13.2 [पृष्ठ ३२]

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आरडी शर्मा Mathematics [English] Class 11
पाठ 13 Complex Numbers
Exercise 13.2 | Q 6.1 | पृष्ठ ३२

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