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Solve the Equation: x^(2)-x+1+i=0....

Solve the Equation:
`x^(2)-x+1+i=0`.

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To solve the equation \( x^2 - x + 1 + i = 0 \), we can follow these steps: ### Step 1: Rearranging the Equation First, we can rewrite the equation in standard quadratic form: \[ x^2 - x + (1 + i) = 0 \] Here, we identify \( a = 1 \), \( b = -1 \), and \( c = 1 + i \). ### Step 2: Applying the Quadratic Formula We will use the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] Substituting the values of \( a \), \( b \), and \( c \): \[ x = \frac{-(-1) \pm \sqrt{(-1)^2 - 4 \cdot 1 \cdot (1 + i)}}{2 \cdot 1} \] This simplifies to: \[ x = \frac{1 \pm \sqrt{1 - 4(1 + i)}}{2} \] ### Step 3: Simplifying the Discriminant Now, we simplify the discriminant: \[ 1 - 4(1 + i) = 1 - 4 - 4i = -3 - 4i \] Thus, we have: \[ x = \frac{1 \pm \sqrt{-3 - 4i}}{2} \] ### Step 4: Finding the Square Root of a Complex Number Let \( z = x + iy \) such that \( z^2 = -3 - 4i \). Expanding \( z^2 \): \[ (x + iy)^2 = x^2 - y^2 + 2xyi = -3 - 4i \] From this, we can equate the real and imaginary parts: 1. \( x^2 - y^2 = -3 \) 2. \( 2xy = -4 \) ### Step 5: Solving the System of Equations From the second equation, we can express \( y \) in terms of \( x \): \[ y = \frac{-4}{2x} = \frac{-2}{x} \] Substituting \( y \) into the first equation: \[ x^2 - \left(\frac{-2}{x}\right)^2 = -3 \] This simplifies to: \[ x^2 - \frac{4}{x^2} = -3 \] Multiplying through by \( x^2 \) to eliminate the fraction: \[ x^4 + 3x^2 - 4 = 0 \] ### Step 6: Letting \( u = x^2 \) Let \( u = x^2 \). The equation becomes: \[ u^2 + 3u - 4 = 0 \] Using the quadratic formula: \[ u = \frac{-3 \pm \sqrt{3^2 - 4 \cdot 1 \cdot (-4)}}{2 \cdot 1} = \frac{-3 \pm \sqrt{9 + 16}}{2} = \frac{-3 \pm 5}{2} \] This gives us: \[ u = 1 \quad \text{or} \quad u = -4 \] Since \( u = x^2 \), we discard \( u = -4 \) (as \( x^2 \) cannot be negative) and take \( u = 1 \): \[ x^2 = 1 \implies x = 1 \quad \text{or} \quad x = -1 \] ### Step 7: Finding Corresponding \( y \) Values Using \( y = \frac{-2}{x} \): 1. If \( x = 1 \): \( y = -2 \) 2. If \( x = -1 \): \( y = 2 \) ### Step 8: Finding Values of \( z \) Thus, the values of \( z \) are: 1. \( z = 1 - 2i \) 2. \( z = -1 + 2i \) ### Step 9: Final Values of \( x \) Substituting back into our expression for \( x \): \[ x = \frac{1 \pm z}{2} \] This gives us: 1. \( x = \frac{1 + (1 - 2i)}{2} = 1 - i \) 2. \( x = \frac{1 + (-1 + 2i)}{2} = i \) ### Conclusion The solutions to the equation \( x^2 - x + 1 + i = 0 \) are: \[ x = 1 - i \quad \text{and} \quad x = i \]
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