In Exercises 21–40, eliminate the parameter t. Then use the rectangular equation to sketch the plane curve represented by the given parametric equations. Use arrows to show the orientation of the curve corresponding to increasing values of t. (If an interval for t is not specified, assume that −∞ < t < ∞. x = 2ᵗ, y = 2⁻ᵗ; t ≥ 0
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations

All textbooks
Blitzer 3rd Edition
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Problem 41
Blitzer 3rd Edition
Ch. 5 - Complex Numbers, Polar Coordinates and Parametric Equations
Problem 41Chapter 5, Problem 41
In Exercises 37–52, perform the indicated operations and write the result in standard form. __ (−2 + √−4)²
Verified step by step guidance1
Recognize that the expression involves a complex number: \(-2 + \sqrt{-4}\). Since \(\sqrt{-4} = 2i\), rewrite the expression as \((-2 + 2i)^2\).
Recall the formula for squaring a binomial: \((a + b)^2 = a^2 + 2ab + b^2\). Here, \(a = -2\) and \(b = 2i\).
Calculate each term separately: \(a^2 = (-2)^2\), \(2ab = 2 \times (-2) \times 2i\), and \(b^2 = (2i)^2\).
Simplify each term: \((-2)^2 = 4\), \(2 \times (-2) \times 2i = -8i\), and \((2i)^2 = 4i^2\). Remember that \(i^2 = -1\), so \(4i^2 = 4 \times (-1) = -4\).
Combine all terms: \$4 - 8i - 4\(. Then, simplify the real parts \)4 - 4\( and write the expression in standard form \)a + bi$.

Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
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 √-4 requires recognizing that √-4 = 2i.
Recommended video:
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 these rules.
Recommended video:
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.
Recommended video:
Complex Numbers In Polar Form
Related Practice
Textbook Question
772
views
Textbook Question
In Exercises 35–44, test for symmetry and then graph each polar equation. r = 1 / 1−cos θ
736
views
Textbook Question
In Exercises 41–48, the rectangular coordinates of a point are given. Find polar coordinates of each point. Express θ in radians. (−2, 2)
794
views
Textbook Question
In Exercises 41–48, the rectangular coordinates of a point are given. Find polar coordinates of each point. Express θ in radians. _ (2,−2√3)
720
views
Textbook Question
In Exercises 37–52, perform the indicated operations and write the result in standard form. ___ ___ 5√−16 + 3√−81
678
views
Textbook Question
In Exercises 37–44, find the product of the complex numbers. Leave answers in polar form. z₁ = cos π/4 + i sin π/4 z₂ = cos π/3 + i sin π/3
545
views