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If X + I Y = a + I B a − I B Prove that X2 + Y2 = 1. - Mathematics

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प्रश्न

If \[x + iy = \frac{a + ib}{a - ib}\] prove that x2 + y2 = 1.

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उत्तर

\[x + iy = \frac{a + ib}{a - ib}\]

\[\text { Taking mod on both the sides }: \]

\[\left| x + iy \right| = \left| \frac{a + ib}{a - ib} \right|\]

\[ \Rightarrow \sqrt{x^2 + y^2} = \frac{\sqrt{a^2 + b^2}}{\sqrt{a^2 + b^2}}\]

\[ \Rightarrow \sqrt{x^2 + y^2} = 1\]

\[ \Rightarrow x^2 + y^2 = 1\]

\[\text { Hence proved } .\]

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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 8 | पृष्ठ ३२

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