Perform each operation. Write answers in standard form. (5-11i)(5+11i)

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Recognize that the expression is a product of two complex conjugates: $(5 - 11i)(5 + 11i)$.

Recall the formula for the product of conjugates: $(a - bi)(a + bi) = a^2 + b^2$, where $a = 5$ and $b = 11$.

Calculate $a^2$ which is \$5^2$ and $b^2$ which is $11^2$ separately.

Add the results from the previous step to get $a^2 + b^2$.

Write the final answer in standard form $x + yi$, noting that the imaginary part will be zero because the product of conjugates is a real number.

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Key Concepts

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

Complex Numbers and Standard Form

Complex numbers are expressed in the form a + bi, where a is the real part and b is the imaginary part. The standard form means writing the answer explicitly as a sum of a real number and an imaginary number. Understanding this form is essential for correctly presenting the result of operations involving complex numbers.

Multiplication of Complex Numbers

To multiply complex numbers, use the distributive property (FOIL method) to expand the product. Multiply each term in the first complex number by each term in the second, remembering that i² = -1. This process combines like terms to simplify the expression.

Simplifying Using i² = -1

Since i is the imaginary unit, i² equals -1. This identity allows you to convert powers of i into real numbers, simplifying expressions involving complex numbers. Applying this rule is crucial when combining terms after multiplication.

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