Greetings!
"10-3" can also be written as:
1) -3+10
2)10+(-3)
Hope this helps.
-Benjamin
Answer:

Step-by-step explanation:
Given that alpha and beta be conjugate complex numbers
such that frac{\alpha}{\beta^2} is a real number and alpha - \beta| = 2 \sqrt{3}.
Let

since they are conjugates


Imaginary part of the above =0
i.e. 
So the value of alpha = 
c^2 = a^2 + b^2 - 2(ab)(cos C)
c^2 + 2(ab)(cos C) = a^2 + b^2
2(ab)(cos C) = a^2 + b^2 - c^2
cos C = (a^2 + b^2 - c^2) / 2ab - Answer choice E
Hope this helps! :)
The graph is shown below. I used GeoGebra to create the graph. The graph is restricted on the domain
meaning that everything to the left of x = 0 is not drawn, and the same for everything to the right of x = 2.
A table of values is included as well. Each row in the table represents an ordered pair point (x,y) that is on the blue cosine graph.