Skip to main content
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601당신이 사용하는 게 아니라요?교과서 변경
5장, 문제 9

Perform the indicated operations and write the result in standard form. (−2 + √−100)²

검증된 단계별 안내
1
Recognize that the expression involves a complex number because of the square root of a negative number: \(\sqrt{-100}\). Recall that \(\sqrt{-1} = i\), where \(i\) is the imaginary unit.
Rewrite \(\sqrt{-100}\) as \(\sqrt{100} \times \sqrt{-1} = 10i\). So the expression becomes \((-2 + 10i)^2\).
Use the formula for squaring a binomial: \((a + b)^2 = a^2 + 2ab + b^2\). Here, \(a = -2\) and \(b = 10i\).
Calculate each term separately: \(a^2 = (-2)^2\), \(2ab = 2 \times (-2) \times 10i\), and \(b^2 = (10i)^2\).
Combine the results and simplify, remembering that \(i^2 = -1\), to write the final expression in standard form \(a + bi\), where \(a\) and \(b\) are real numbers.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
4m
도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Complex Numbers and Imaginary Unit

Complex numbers consist of a real part and an imaginary part, expressed as a + bi, where i is the imaginary unit with the property i² = -1. Understanding how to interpret and manipulate expressions involving √-100 requires recognizing that √-100 = 10i.
추천 영상:
3:31
Introduction to Complex Numbers

Operations with Complex Numbers

Performing operations like addition, multiplication, and exponentiation on complex numbers follows algebraic rules, treating i as a variable but applying i² = -1 to simplify. Squaring a complex number involves expanding the binomial and simplifying using this property.
추천 영상:
4:22
Dividing Complex Numbers

Standard Form of a Complex Number

The standard form of a complex number is a + bi, where a and b are real numbers. After performing operations, the result should be simplified and expressed clearly in this form, separating the real and imaginary parts.
추천 영상:
04:47
Complex Numbers In Polar Form