Question

Express the following division in the form of a + bi: (1+3i)(2+i)

Answer 1

Answer:

$(1 + i\,3) \cdot (2 + i) = -1 + i\,7$

Step-by-step explanation:

We proceed to present the procedure by algebraic means:

1) $(1 + i\,3)\cdot (2 + i)$ Given

2) $2\cdot (1 + i\,3) + i\,(1+i\,3)$ Distributive and Commutative Properties

3) $2 + i\,6 + i + i^{2} \,3$ Distributive, Commutative and Associative Properties

4) $2 + i\,7 -3$ Definition of imaginary number/Distributive, Commutative and Associative Properties

5) $-1 + i\,7$ Commutative and Associative Properties