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Express the Following Complex Number in the Standard Form a + I B: 2 + 3 I 4 + 5 I

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Question

Express the following complex number in the standard form a + i b:

\[\frac{2 + 3i}{4 + 5i}\]

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Solution

\[ \frac{2 + 3i}{4 + 5i}\]

\[ = \frac{2 + 3i}{4 + 5i} \times \frac{4 - 5i}{4 - 5i}\]

\[ = \frac{8 - 10i + 12i - 15 i^2}{16 - 25 i^2} \left( \because i^2 = - 1 \right)\]

\[ = \frac{23 + 2i}{16 + 25}\]

\[ = \frac{23}{41} + \frac{2}{41}i\]

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Chapter 13: Complex Numbers - Exercise 13.2 [Page 31]

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R.D. Sharma Mathematics [English] Class 11
Chapter 13 Complex Numbers
Exercise 13.2 | Q 1.07 | Page 31

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