Question

Which of the following is equivalent to
the expression (i + 5)(3 + 4i)?

Answer 1

Answer: 11+23i

Explanation:

(i+5)(3+4i)

First foil

3i+4i^2 +15+20i

Then combine like terms

23i+15+4i^2

i^2 = -1 so,

23i+15+4(-1)

11+23i