Evaluate x² − 2x + 2 for x = 1 + i.

Verified step by step guidance

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 $i^2 = -1$.

Substitute $x = 1 + i$ into the expression to get: $(1 + i)^2 - 2(1 + i) + 2$.

Expand the squared term using the formula $(a + b)^2 = a^2 + 2ab + b^2$: $(1 + i)^2 = 1^2 + 2 \cdot 1 \cdot i + i^2 = 1 + 2i + i^2$.

Replace $i^2$ with $-1$ and simplify the expression inside the parentheses: \$1 + 2i + (-1) = 2i$.

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.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

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.

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