Find all values of (1+i)^(1-i) in the form a + bi.

Answer: e(12ln⁡2+π4+2nπ)[cos⁡(π4+2nπ−12ln⁡2)+isin⁡(π4+2nπ−12ln⁡2)]e^{\left( \frac{1}{2}\ln 2 + \frac{\pi}{4} + 2n\pi \right)} \left[ \cos\left( \frac{\pi}{4} + 2n\pi - \frac{1}{2}\ln 2 \right) + i \sin\left( \frac{\pi}{4} + 2n\pi - \frac{1}{2}\ln 2 \right) \right] for n∈Zn \in \mathbb{Z}

Step-by-step solution

Step 1: Express the base in polar form

First, we express the base 1+i1+i in its polar form. The magnitude is r=12+12=2r = \sqrt{1^2 + 1^2} = \sqrt{2}, and the argument is θ=arctan⁡(11)=π4\theta = \arctan\left(\frac{1}{1}\right) = \frac{\pi}{4}. So, 1+i=2eiπ41+i = \sqrt{2} e^{i\frac{\pi}{4}}. We also need to consider the general form including 2nπ2n\pi for the argument, so 1+i=2ei(π4+2nπ)1+i = \sqrt{2} e^{i(\frac{\pi}{4} + 2n\pi)} for integer nn.

Step 2: Apply the definition of complex exponentiation

We use the general definition of complex exponentiation, which states that zw=ewln⁡zz^w = e^{w \ln z}. Here, z=1+iz = 1+i and w=1−iw = 1-i. The natural logarithm of a complex number z=reiθz = re^{i\theta} is ln⁡z=ln⁡r+iθ\ln z = \ln r + i\theta.

Step 3: Calculate wln⁡zw \ln z

Substitute the values of ww and ln⁡z\ln z into the expression wln⁡zw \ln z. We have w=1−iw = 1-i and ln⁡z=ln⁡2+i(π4+2nπ)=12ln⁡2+i(π4+2nπ)\ln z = \ln\sqrt{2} + i\left(\frac{\pi}{4} + 2n\pi\right) = \frac{1}{2}\ln 2 + i\left(\frac{\pi}{4} + 2n\pi\right). Multiply these two complex numbers and group the real and imaginary parts.

Step 4: Substitute into ewln⁡ze^{w \ln z}

Now we substitute the calculated value of wln⁡zw \ln z back into the exponential form ewln⁡ze^{w \ln z}. This gives us the general form of (1+i)(1−i)(1+i)^{(1-i)}.

Step 5: Separate into real and imaginary parts

Using Euler's formula, eA+Bi=eA(cos⁡B+isin⁡B)e^{A+Bi} = e^A (\cos B + i \sin B), we separate the expression into its real and imaginary components. Here, A=12ln⁡2+π4+2nπA = \frac{1}{2}\ln 2 + \frac{\pi}{4} + 2n\pi and B=π4+2nπ−12ln⁡2B = \frac{\pi}{4} + 2n\pi - \frac{1}{2}\ln 2. This gives the final form a+bia+bi.

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