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Step 1:

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(a)

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The complex conjugate of the number is $\"\"$ .

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Euler $\"\"$ s formula: $\"\"$ .

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Rewrite the complex conjugate $\"\"$ .

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The complex conjugate $\"\"$ \ \

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(b)

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The complex conjugate is $\"\"$ .

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From Euler $\"\"$ s formula,

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$\"\"$

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Hence,

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$\"\"$

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Solution:

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$\"\"$

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