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Evaluate the Following: X 4 − 4 X 3 + 4 X 2 + 8 X + 44 , When X = 3 + 2 I - Mathematics

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प्रश्न

Evaluate the following:

\[x^4 - 4 x^3 + 4 x^2 + 8x + 44,\text {  when } x = 3 + 2i\]

उत्तर

\[x = 3 + 2i\]

\[ \Rightarrow x^2 = \left( 3 + 2i \right)^2 \]

\[ = 9 + 4 i^2 + 12i\]

\[ = 5 + 12i\]

\[ \Rightarrow x^3 = x^2 \times x\]

\[ = \left( 5 + 12i \right) \times \left( 3 + 2i \right)\]

\[ = 15 + 10i + 36i - 24\]

\[ = - 9 + 46i\]

\[ \Rightarrow x^4 = \left( x^2 \right)^2 \]

\[ = \left( 5 + 12i \right)^2 \]

\[ = 25 + 144 i^2 + 120i\]

\[ = - 119 + 120i\]

\[ \Rightarrow x^4 - 4 x^3 + 4 x^2 + 8x + 44 = - 119 + 120i - 4\left( - 9 + 46i \right) + 4\left( 5 + 12i \right) + 8\left( 3 + 2i \right) + 44\]

\[ = - 119 + 120i + 36 - 184i + 20 + 48i + 24 + 16i + 44\]

\[ = 5\]

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

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आरडी शर्मा Mathematics [English] Class 11
अध्याय 13 Complex Numbers
Exercise 13.2 | Q 16.2 | पृष्ठ ३२

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