Question

the expression 10/(3 + i) is equivalent to:

1) 3 - i
2) (15 + 5i)/4
3) 3 + i
4) 5/4

Answer 1

\[\frac{10}{3+i}=10\frac{1}{3+i}=10\frac{1}{3+i} \times \frac{3-i}{3-i}=10\frac{3-i}{3^2-i^2}=10\frac{3-i}{10}\]

Answer 2

\[=3-i\]

Answer 3

Your first available choice.