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Find the Value of the Following Expression:I30 + I80 + I120 - Mathematics

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प्रश्न

Find the value of the following expression:

i30 + i80 + i120

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उत्तर

\[\ i^{30} + i^{80} + i^{120} \]

\[ = i^{4 \times 7 + 2} + i^{4 \times 20} + i^{4 \times 30} \]

\[ = \left\{ \left( i^4 \right)^7 \times i^2 \right\} + \left\{ \left( i^4 \right)^{20} \right\} + \left\{ \left( i^4 \right)^{30} \right\}\]

\[ = i^2 + 1 + 1 \left[ \because i^4 = 1 \right]\]

\[ = - 1 + 2 \left[ \because i^2 = - 1 \right] \]

\[ = 1\]

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अध्याय 13: Complex Numbers - Exercise 13.1 [पृष्ठ ४]

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आरडी शर्मा Mathematics [English] Class 11
अध्याय 13 Complex Numbers
Exercise 13.1 | Q 3.2 | पृष्ठ ४

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