Chapter 3
Precalculus · 674 exercises
Problem 1
Explain how to add complex numbers
6 step solution
Problem 2
What is the basic principle in multiplication of complex numbers?
4 step solution
Problem 3
Give an example to show the product of two imaginary numbers is not always imaginary
4 step solution
Problem 4
What is a characteristic of the plot of a real number in the complex plane?
3 step solution
Problem 5
Evaluate the algebraic expressions. If \(f(x)=x^{2}+x-4,\) evaluate \(f(2 i)\)
5 step solution
Problem 6
Evaluate the algebraic expressions. If \(f(x)=x^{3}-2,\) evaluate \(f(i)\)
2 step solution
Problem 7
Evaluate the algebraic expressions. If \(f(x)=x^{2}+3 x+5,\) evaluate \(f(2+i)\)
5 step solution
Problem 8
Evaluate the algebraic expressions. If \(f(x)=2 x^{2}+x-3,\) evaluate \(f(2-3 i)\)
7 step solution
Problem 9
Evaluate the algebraic expressions. If \(f(x)=\frac{x+1}{2-x},\) evaluate \(f(5 i)\)
6 step solution
Problem 10
Evaluate the algebraic expressions. If \(f(x)=\frac{1+2 x}{x+3},\) evaluate \(f(4 i)\)
10 step solution
Problem 13
Plot the complex numbers on the complex plane. \(1-2 i\)
5 step solution
Problem 14
Plot the complex numbers on the complex plane. \(-2+3 i\)
3 step solution
Problem 15
Plot the complex numbers on the complex plane. \(i\)
4 step solution
Problem 16
Plot the complex numbers on the complex plane. \(-3-4 i\)
5 step solution
Problem 17
Perform the indicated operation and express the result as a simplified complex number. \((3+2 i)+(5-3 i)\)
4 step solution
Problem 18
Perform the indicated operation and express the result as a simplified complex number. \((-2-4 i)+(1+6 i)\)
4 step solution
Problem 19
Perform the indicated operation and express the result as a simplified complex number. \((-5+3 i)-(6-i)\)
6 step solution
Problem 20
Perform the indicated operation and express the result as a simplified complex number. \((2-3 i)-(3+2 i)\)
5 step solution
Problem 21
Perform the indicated operation and express the result as a simplified complex number. \((-4+4 i)-(-6+9 i)\)
5 step solution
Problem 22
Perform the indicated operation and express the result as a simplified complex number. \((2+3 i)(4 i)\)
4 step solution
Problem 23
Perform the indicated operation and express the result as a simplified complex number. \((5-2 i)(3 i)\)
4 step solution
Problem 24
For the following exercises, perform the indicated operation and express the result as a simplified complex number \((6-2 i)(5)\)
4 step solution
Problem 25
Perform the indicated operation and express the result as a simplified complex number. \((-2+4 i)(8)\)
5 step solution
Problem 26
Perform the indicated operation and express the result as a simplified complex number. \((2+3 i)(4-i)\)
4 step solution
Problem 27
Perform the indicated operation and express the result as a simplified complex number. \((-1+2 i)(-2+3 i)\)
4 step solution
Problem 28
Perform the indicated operation and express the result as a simplified complex number. \((4-2 i)(4+2 i)\)
5 step solution
Problem 29
Perform the indicated operation and express the result as a simplified complex number. \((3+4 i)(3-4 i)\)
5 step solution
Problem 30
Perform the indicated operation and express the result as a simplified complex number. \(\frac{3+4 i}{2}\)
3 step solution
Problem 31
Perform the indicated operation and express the result as a simplified complex number. \(\frac{6-2 i}{3}\)
4 step solution
Problem 32
Perform the indicated operation and express the result as a simplified complex number. \(\frac{-5+3 i}{2 i}\)
6 step solution
Problem 33
Perform the indicated operation and express the result as a simplified complex number. \(\frac{6+4 i}{i}\)
3 step solution
Problem 34
Perform the indicated operation and express the result as a simplified complex number. \(\frac{2-3 i}{4+3 i}\)
5 step solution
Problem 35
Perform the indicated operation and express the result as a simplified complex number. \(\frac{3+4 i}{2-i}\)
5 step solution
Problem 36
Perform the indicated operation and express the result as a simplified complex number. \(\frac{2+3 i}{2-3 i}\)
5 step solution
Problem 37
Perform the indicated operation and express the result as a simplified complex number. \(\sqrt{-9}+3 \sqrt{-16}\)
3 step solution
Problem 38
Perform the indicated operation and express the result as a simplified complex number. \(-\sqrt{-4}-4 \sqrt{-25}\)
5 step solution
Problem 39
Perform the indicated operation and express the result as a simplified complex number. \(\frac{2+\sqrt{-12}}{2}\)
3 step solution
Problem 40
Perform the indicated operation and express the result as a simplified complex number. \(\frac{4+\sqrt{-20}}{2}\)
4 step solution
Problem 41
Perform the indicated operation and express the result as a simplified complex number. \(i^{8}\)
3 step solution
Problem 42
Perform the indicated operation and express the result as a simplified complex number. \(i^{15}\)
3 step solution
Problem 43
Perform the indicated operation and express the result as a simplified complex number. \(i^{22}\)
4 step solution
Problem 44
Use a calculator to help answer the questions. Evaluate \((1+i)^{k}\) for \(k=4,8,\) and \(12 .\) Predict the value if \(k=16\)
6 step solution
Problem 45
Use a calculator to help answer the questions. Evaluate \((1-i)^{k}\) for \(k=2,6,\) and \(10 .\) Predict the value if \(k=14\)
4 step solution
Problem 46
Use a calculator to help answer the questions. Evaluate \((1+i)^{k}-(1-i)^{k}\) for \(k=4,8,\) and \(12 .\) Predict the value for \(k=16\)
5 step solution
Problem 47
Use a calculator to help answer the questions. Show that a solution of \(x^{6}+1=0\) is \(\frac{\sqrt{3}}{2}+\frac{1}{2} i\)
3 step solution
Problem 48
Use a calculator to help answer the questions. Show that a solution of \(x^{8}-1=0\) is \(\frac{\sqrt{2}}{2}+\frac{\sqrt{2}}{2} i\)
5 step solution
Problem 49
Evaluate the expressions, writing the result as a simplified complex number. \(\frac{1}{i}+\frac{4}{i^{3}}\)
5 step solution
Problem 50
Evaluate the expressions, writing the result as a simplified complex number. \(\frac{1}{i^{11}}-\frac{1}{i^{21}}\)
6 step solution
Problem 51
Evaluate the expressions, writing the result as a simplified complex number. \(i^{7}\left(1+i^{2}\right)\)
4 step solution
Problem 52
Evaluate the expressions, writing the result as a simplified complex number. \(i^{-3}+5 i^{7}\)
4 step solution