The types of problems this program will solve are:
To multiply two binomials together, use FOIL.
(5 + 3i)(3 + 2i)
F + O + I + L
15 + 10i + 9i + 6i2
15 + 19i + 6i2
15 + 19i + 6(-1)
15 + 9i - 6
15 - 6 + 9i
9 + 9i *Answer
Multiply: (7 - 6i)(4 + 8i)
F + O + I + L
28 + 56i + -24i + -48i2
28 + 32i - 48i2
28 + 32i - 48(-1)
28 + 32i + 48
28 + 48 + 32i
76 + 32i * Answer
Multiply: (4 - 2i)(5 + 3i)
F + O + I + L
20 + 12i + -10i + -6i2
20 + 2i + -6i2
20 + 2i - 6i2
20 + 2i - 6(-1)
20 + 2i + 6
20 + 6 + 2i
26 + 2i *Answer
Rule:
The last term in FOIL always ends with i2.
In previous lessons it was established that i2 is always equal to -1. When simplifying the expression you must replace i2 with -1. Then, continue combining like terms.
The constant term must come first in the answer, then the variable term with "i" in it.