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Determine the conjugate and the reciproc...

Determine the conjugate and the reciprocal of each complex number given below:
`i^(3)`

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To determine the conjugate and the reciprocal of the complex number \( i^3 \), we will follow these steps: ### Step 1: Calculate \( i^3 \) We know that \( i \) is the imaginary unit, defined as \( i = \sqrt{-1} \). The powers of \( i \) cycle every four terms: - \( i^1 = i \) - \( i^2 = -1 \) - \( i^3 = -i \) - \( i^4 = 1 \) Thus, we can calculate: \[ i^3 = -i \] ### Step 2: Find the Conjugate The conjugate of a complex number \( a + bi \) is given by \( a - bi \). For our case: - The complex number is \( 0 - i \) (which can be rewritten as \( 0 + (-1)i \)). - Therefore, the conjugate of \( -i \) is: \[ \text{Conjugate of } -i = 0 + i = i \] ### Step 3: Find the Reciprocal The reciprocal of a complex number \( z = a + bi \) is given by: \[ \frac{1}{z} = \frac{1}{a + bi} = \frac{a - bi}{a^2 + b^2} \] For \( z = -i \): - Here, \( a = 0 \) and \( b = -1 \). - Thus, \( a^2 + b^2 = 0^2 + (-1)^2 = 1 \). - The reciprocal becomes: \[ \frac{1}{-i} = \frac{0 + i}{1} = i \] ### Final Results - The conjugate of \( i^3 \) (which is \( -i \)) is \( i \). - The reciprocal of \( i^3 \) (which is \( -i \)) is \( i \). ### Summary - Conjugate: \( i \) - Reciprocal: \( i \)
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