please show work 10 points
2007-01-28 08:28:24 · 4 answers · asked by grim reaper 2 in Science & Mathematics ➔ Mathematics
first FOIL to multiply out
6-3i+30i-15i^2
combine like terms
6+27i-15i^2
i^2=-1
so 6+27i-15(-1)
=6+27i+15...final answer
2007-01-28 08:35:51 · answer #1 · answered by dla68 4 · 0⤊ 1⤋
Simplifying
(1 + 5i)(6 + -3i)
Multiply (1 + 5i) * (6 + -3i)
(1(6 + -3i) + 5i * (6 + -3i))
((6 * 1 + -3i * 1) + 5i * (6 + -3i))
((6 + -3i) + 5i * (6 + -3i))
(6 + -3i + (6 * 5i + -3i * 5i))
(6 + -3i + (30i + -15i^2))
Combine like terms: -3i + 30i = 27i
(6 + 27i + -15i^2)
2007-01-28 16:48:33 · answer #2 · answered by SHIBZ 2 · 0⤊ 1⤋
(1+5i)(6-3i)....
First: use the foiling method....
[(1)(6) + (1)(-3i)] + [(5i)(6) + (5i)(-3i)]
[6 - 3i] + [30i - 15i^2]
6 - 3i + 30i - 15i^2
Sec: combine "like" terms...
6 + 27i - 15i^2
Third: the "i^2" becomes "-1"...
6 + 27i - 15(-1)
6 + 27i - (-15)
6 + 27i + 15
= 21 + 27i
2007-01-28 21:04:41 · answer #3 · answered by ♪♥Annie♥♪ 6 · 0⤊ 0⤋
(1 + 5i)(6 - 3i) =
6 + 30i - 3i - 15i²
6 + 27i - 15(- 1)
6 + 27i+15
21 + 27i
- - - - - - - - - -s-
-
2007-01-28 16:50:13 · answer #4 · answered by SAMUEL D 7 · 1⤊ 0⤋