Drag each expression to the correct location in the table.

Determine which expressions represent real numbers and which expressions represent complex numbers.

\begin{tabular}{|l|l|}
\hline Real Numbers & Complex Numbers \\
\hline
[tex]$\sqrt{(-3)^2}$[/tex] & [tex]$-2+5i$[/tex] \\
[tex]$i^4$[/tex] & [tex]$\sqrt{-3}$[/tex] \\
[tex]$409$[/tex] & [tex]$7i^2+6i^3$[/tex] \\
[tex]$-1+3i^2$[/tex] & [tex]$0+4i$[/tex] \\
& \\
\hline
\end{tabular}

Expressions:
[tex]\[
\sqrt{(-3)^2} \quad -2+5i \quad i^4 \quad \sqrt{-3} \quad 7i^2+6i^3 \quad 0+4i \quad -1+3i^2 \quad 409
\][/tex]



Answer :

To classify each expression as either a real number or a complex number, let us examine them individually:

1. [tex]\(\sqrt{(-3)^2}\)[/tex]:
- Calculate [tex]\( (-3)^2 \)[/tex]: [tex]\( (-3)^2 = 9 \)[/tex].
- Then, take the square root of 9: [tex]\( \sqrt{9} = 3 \)[/tex].
- This is a real number.

2. [tex]\( -2 + 5i \)[/tex]:
- This expression has both a real part ([tex]\(-2\)[/tex]) and an imaginary part ([tex]\(5i\)[/tex]).
- This is a complex number.

3. [tex]\( i^4 \)[/tex]:
- Considering the powers of [tex]\( i \)[/tex]:
- [tex]\( i^2 = -1 \)[/tex]
- [tex]\( i^4 = (i^2)^2 = (-1)^2 = 1 \)[/tex]
- This is a real number.

4. [tex]\( \sqrt{-3} \)[/tex]:
- The square root of a negative number involves [tex]\( i \)[/tex].
- Specifically, [tex]\( \sqrt{-3} = \sqrt{3}i \)[/tex].
- This is a complex number.

5. [tex]\( 7i^2 + 6i^3 \)[/tex]:
- Calculate [tex]\( i^2 \)[/tex]: [tex]\( i^2 = -1 \)[/tex].
- Calculate [tex]\( i^3 \)[/tex]: [tex]\( i^3 = i^2 \cdot i = -i \)[/tex].
- So, [tex]\( 7i^2 = 7(-1) = -7 \)[/tex].
- And, [tex]\( 6i^3 = 6(-i) = -6i \)[/tex].
- Combining: [tex]\( 7i^2 + 6i^3 = -7 - 6i \)[/tex].
- This is a complex number.

6. [tex]\( 0 + 4i \)[/tex]:
- This expression resembles the form [tex]\( a + bi \)[/tex] with [tex]\( a = 0 \)[/tex] and [tex]\( b = 4 \)[/tex].
- This is a complex number.

7. [tex]\( -1 + 3i^2 \)[/tex]:
- Considering [tex]\( i^2 = -1 \)[/tex]:
- Calculate [tex]\( 3i^2 \)[/tex]: [tex]\( 3 \cdot (-1) = -3 \)[/tex].
- So, the expression becomes [tex]\( -1 + (-3) = -4 \)[/tex].
- This is a real number.

8. 409:
- This is a plain real number (an integer).
- This is a real number.

Now, organizing the expressions into their respective categories:

[tex]\[ \begin{tabular}{|l|l|} \hline Real Numbers & Complex Numbers \\ \hline & \\ \sqrt{(-3)^2} & -2 + 5i \\ i^4 & \sqrt{-3} \\ -1 + 3i^2 & 7i^2 + 6i^3 \\ 409 & 0 + 4i \\ & \\ \hline \end{tabular} \][/tex]

So, the final table should be:

[tex]\[ \begin{tabular}{|l|l|} \hline Real Numbers & Complex Numbers \\ \hline \sqrt{(-3)^2} & -2 + 5i \\ i^4 & \sqrt{-3} \\ -1 + 3i^2 & 7i^2 + 6i^3 \\ 409 & 0 + 4i \\ \hline \end{tabular} \][/tex]