Evaluate x² − 2x + 2 for x = 1 + i.

Verified step by step guidance

1. Recognize that the problem involves evaluating the expression \(x^2 - 2x + 2\) where \(x\) is a complex number, specifically \(x = 1 + i\), with \(i\) being the imaginary unit satisfying \(i^2 = -1\).
2. Substitute \(x = 1 + i\) into the expression to get: \((1 + i)^2 - 2(1 + i) + 2\).
3. Expand the squared term using the formula \((a + b)^2 = a^2 + 2ab + b^2\): \((1 + i)^2 = 1^2 + 2 \cdot 1 \cdot i + i^2 = 1 + 2i + i^2\).
4. Replace \(i^2\) with \(-1\) and simplify the expression inside the parentheses: \$1 + 2i + (-1) = 2i$.
5. Now, substitute back and simplify the entire expression step-by-step: \$2i - 2(1 + i) + 2$. Expand the multiplication and combine like terms to simplify the expression fully.

Key Concepts

Complex Numbers

Complex numbers are numbers of the form a + bi, where a and b are real numbers and i is the imaginary unit with the property i² = -1. Understanding how to perform arithmetic operations with complex numbers is essential for evaluating expressions involving them.

Substitution in Algebraic Expressions

Substitution involves replacing a variable in an expression with a given value. In this case, substituting the complex number x = 1 + i into the polynomial allows evaluation of the expression for that specific input.

Simplification of Expressions with Imaginary Units

Simplifying expressions with imaginary units requires applying the rule i² = -1 and combining like terms carefully. This process ensures the expression is reduced to its simplest form, often resulting in a complex number in standard form a + bi.