Question

Work with a partner. Determine which subsets of the set of complex numbers

contain each number.
a. √—
9 b. √—

0 c. −√—
4

d. √
—
4
—
9
e. √—

2 f. √—
−1

Answer 1

a.√—9 is the set of all complex numbers whose square is -9. This set contains two numbers: 3i and -3i, where i is the imaginary unit.

b.√—0 is not a valid mathematical expression, as the square root of 0 is 0 and cannot be negative.

c.−√—4 is the set of all complex numbers whose square is 4. This set contains two numbers: 2 and -2, which are both real numbers.

d.√—4—9 is not a valid mathematical expression. The square root operator can only be applied to non-negative real numbers.

e.√—2 is the set of all complex numbers whose square is -2. This set contains two numbers: √—2i and -√—2i, where i is the imaginary unit.

f.√—−1 is the set of all complex numbers whose square is -1. This set contains two numbers: i and -i, where i is the imaginary unit.