Complex Number System

What is the definition of an imaginary number?

• x

• -1

• √-1

• origin

Classify the following:
√-9

• real

• imaginary

• rational

• whole

• complex numbers

• real part of a complex number

• imaginary part of a complex number

• imaginary numbers

• pure imaginary number

• real part of a complex number

• imaginary part of a complex number

• imaginary numbers

• pure imaginary number

• complex numbers

What is a complex number?

• A number that can be expressed in the form a + bi, where a and b are real numbers, and i is the imaginary unit.

• A number that can only be expressed in the form a - bi

• A number that has no real part

• A number that can only be expressed in the form a + bi

Answer explanation

A complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is the imaginary unit. This choice correctly defines a complex number.

• 2

• -2

• 4i

• -4i

• 2i

• -2i

The set of ​ (a)   is the set of all numbers written in the

form a + bi, where a and b are real numbers and b is not equal to 0.​

• imaginary numbers

• complex numbers

• real part of a complex number

• imaginary part of a complex number

• pure imaginary number

A ​ (a)   is a number of the form a + bi, where a is equal to 0 and b is not equal to 0.

• pure imaginary number

• complex numbers

• real part of a complex number

• imaginary part of a complex number

• imaginary numbers

Which set does this symbol represent?

• Complex

• Real

• Imaginary

• Rational

• Irrational