Question

Simplify the expression

(1-3i)(2+5i)-(3-12i).

Show your work.

Answer 1

14 +11i

Explanation:

The product of binomials is found in the usual way, except that i² = -1.

(1 -3i)(2 +5i) -(3 -12i)

= (1·2 +1·5i -3i·2 -3i·5i) -3 +12i

= (2 +15 -3) +i(5 -6 +12)

= 14 +11i