A complex number has a real and an imaginary part
is a complex number
A complex number is represented as:
Where:
<em />
<em> real</em>
<em />
<em> imaginary</em>
<em />
By comparing the options to ;
and 
are not complex numbers
This is so because they do not have imaginary parts
However,
is a complex number
Because; 9i is imaginary
Read more about complex numbers at:
brainly.com/question/19007885
Answer:
6.9 I think.
Step-by-step explanation:
I feel like it’s d because it is changed to the other form
The point on the unit circle corresponding to -180 degrees is
((x, y) = (-1, 0).
<span>tan(-180°) = y/x = 0/(-1) = 0</span>
