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What is the value of (-sqrt(-1))^(4n+3)...

What is the value of `(-sqrt(-1))^(4n+3)+(i^(41)+1^(-257))^(9),` when n inN` ?

A

0

B

1

C

It is parallel to the y-axis

D

`-i`

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The correct Answer is:
To solve the expression \((- \sqrt{-1})^{4n+3} + (i^{41} + 1^{-257})^9\), we can break it down into manageable parts. ### Step-by-Step Solution: 1. **Simplify \(-\sqrt{-1}\)**: \[ -\sqrt{-1} = -i \] Therefore, we rewrite the first part: \[ (-\sqrt{-1})^{4n+3} = (-i)^{4n+3} \] 2. **Use properties of exponents**: The expression \((-i)^{4n+3}\) can be simplified using the fact that \((-i) = e^{-i\frac{\pi}{2}}\): \[ (-i)^{4n+3} = (e^{-i\frac{\pi}{2}})^{4n+3} = e^{-i\frac{\pi}{2}(4n+3)} = e^{-i(2n\pi + \frac{3\pi}{2})} = e^{-i\frac{3\pi}{2}} = i \] 3. **Simplify \(i^{41}\)**: To simplify \(i^{41}\), we can use the periodicity of \(i\) (where \(i^4 = 1\)): \[ i^{41} = i^{4 \cdot 10 + 1} = (i^4)^{10} \cdot i^1 = 1^{10} \cdot i = i \] 4. **Simplify \(1^{-257}\)**: Since any non-zero number raised to a negative exponent is equal to its reciprocal: \[ 1^{-257} = \frac{1}{1^{257}} = 1 \] 5. **Combine \(i^{41}\) and \(1^{-257}\)**: Now we can combine the results: \[ i^{41} + 1^{-257} = i + 1 \] 6. **Raise to the power of 9**: Now we need to find \((i + 1)^9\). First, we can express \(i + 1\) in polar form: \[ i + 1 = \sqrt{2} \left(\cos\frac{\pi}{4} + i\sin\frac{\pi}{4}\right) \] Therefore: \[ (i + 1)^9 = (\sqrt{2})^9 \left(\cos\left(\frac{9\pi}{4}\right) + i\sin\left(\frac{9\pi}{4}\right)\right) \] \[ = 2^{\frac{9}{2}} \left(\cos\left(\frac{9\pi}{4}\right) + i\sin\left(\frac{9\pi}{4}\right)\right) \] 7. **Simplify \(\frac{9\pi}{4}\)**: Since \(\frac{9\pi}{4} = 2\pi + \frac{\pi}{4}\), we have: \[ \cos\left(\frac{9\pi}{4}\right) = \cos\left(\frac{\pi}{4}\right) = \frac{1}{\sqrt{2}}, \quad \sin\left(\frac{9\pi}{4}\right) = \sin\left(\frac{\pi}{4}\right) = \frac{1}{\sqrt{2}} \] 8. **Final calculation**: Thus: \[ (i + 1)^9 = 2^{\frac{9}{2}} \left(\frac{1}{\sqrt{2}} + i\frac{1}{\sqrt{2}}\right) = 2^{\frac{9}{2}} \cdot \frac{1}{\sqrt{2}}(1 + i) = 2^4(1 + i) = 16(1 + i) \] 9. **Combine both parts**: Now we combine both parts: \[ (-i)^{4n+3} + (i + 1)^9 = i + 16(1 + i) = i + 16 + 16i = 16 + 17i \] ### Final Answer: \[ \text{The value is } 16 + 17i. \]

To solve the expression \((- \sqrt{-1})^{4n+3} + (i^{41} + 1^{-257})^9\), we can break it down into manageable parts. ### Step-by-Step Solution: 1. **Simplify \(-\sqrt{-1}\)**: \[ -\sqrt{-1} = -i \] ...
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