Question

Simplify the expression below as much as possible. (6 + 4i ) + (3 - 3i )A.9 + 7iB.9 + iC.3 + iD.3 + 7i

Answer 1

Remember the following rule for adding up two complex numbers:

$(a+bi)+(c+di)=(a+c)+(b+d)i$

The real parts of both numbers add up, the same applies for the imaginary parts.

Then:

$\begin{gathered} (6+4i)+(3-3i)=(6+3)+(4-3)i \\ \\ \therefore(6+4i)+(3-3i)=9+i \end{gathered}$

Therefore, the correct choice is option B) 9+i.