In Exercises 1–10, perform the indicated operations and write the result in standard form. (7 + 8i)(7 − 8i)
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations

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Blitzer 3rd Edition
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Problem 5
Blitzer 3rd Edition
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Problem 5Chapter 5, Problem 5
In Exercises 1–8, add or subtract as indicated and write the result in standard form. 6 − (−5 + 4i) − (−13 − i)
Verified step by step guidance1
Identify the expression to simplify: \(6 - (-5 + 4i) - (-13 - i)\).
Apply the distributive property to remove the parentheses by changing the signs inside each parenthesis preceded by a minus: \(6 + 5 - 4i + 13 + i\).
Group the real parts together and the imaginary parts together: \((6 + 5 + 13) + (-4i + i)\).
Add the real parts: \(6 + 5 + 13\), and add the imaginary parts: \(-4i + i\) separately.
Write the final expression in standard form \(a + bi\), where \(a\) is the sum of the real parts and \(b\) is the sum of the imaginary parts.

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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. Writing a complex number in standard form means presenting it clearly as a sum or difference of its real and imaginary components.
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Complex Numbers In Polar Form
Addition and Subtraction of Complex Numbers
To add or subtract complex numbers, combine their real parts separately and their imaginary parts separately. This process is similar to combining like terms in algebra, ensuring the result remains in standard form.
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Adding and Subtracting Complex Numbers
Handling Negative Signs and Parentheses
When subtracting complex numbers, carefully distribute the negative sign across all terms inside the parentheses. This step is crucial to avoid sign errors and correctly simplify the expression.
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