Help and explain? What's (3 - 4i) (-2 + 6i)?
回答 (6)
2013-03-11 3:05 am
✔ 最佳答案
(3 - 4i)(-2 + 6i)= -6 + 8i + 18i - 24i^2
= -6 + 26i + 24
= 18 + 26i
= 2(9 + 13i)
2013-03-11 3:02 am
(3 - 4i)(-2 + 6i) = -6 + 18i + 8i - 24(i^2)
= -6 + 24 + 26i
= 18 + 26i
= -6 + 24 + 26i
= 18 + 26i
2013-03-14 5:36 pm
(3 - 4i)(- 2 + 6i)
= - 6 + 18i + 8i - 24i^2
= - 6 + 24 + 26i
= 18 + 26i
= 2(9 + 13i) Ans.
= - 6 + 18i + 8i - 24i^2
= - 6 + 24 + 26i
= 18 + 26i
= 2(9 + 13i) Ans.
2013-03-11 3:07 am
FOIL it
Let's try it with x instead of i
(3 - 4x) (-2 + 6x) = -24x^2 + 26x - 6
so
(3 - 4i) (-2 + 6i) = -24i^2 + 26i - 6
But i^2 = -1
So we can simplify further
-24(-1) + 26i - 6 = 18 + 26i
Let's try it with x instead of i
(3 - 4x) (-2 + 6x) = -24x^2 + 26x - 6
so
(3 - 4i) (-2 + 6i) = -24i^2 + 26i - 6
But i^2 = -1
So we can simplify further
-24(-1) + 26i - 6 = 18 + 26i
2013-03-11 3:06 am
(3-4i)(-2+6i)
Use FOIL First outside inner last
3*-2 =-6
3*6i = 18i
-2*-4i = 8i
-4i*6i = 24i^2
= -6 + 18i - 8i - 24i^2
= 2 (-3 + 5i -2i^2)
Factored
Simplify
= -6 +10i - 24i^2
Use FOIL First outside inner last
3*-2 =-6
3*6i = 18i
-2*-4i = 8i
-4i*6i = 24i^2
= -6 + 18i - 8i - 24i^2
= 2 (-3 + 5i -2i^2)
Factored
Simplify
= -6 +10i - 24i^2
2013-03-11 3:05 am
(3-4i)(2-6i)
-------------
Multiply like any 2 binomials.
(3-4i)(2-6i)
= 3(2-6i) - 4i(2-6i)
= 6-18i+-8i+24^2
= 6 - 26i +24*(-1)
= -18 - 26i
-------------
Multiply like any 2 binomials.
(3-4i)(2-6i)
= 3(2-6i) - 4i(2-6i)
= 6-18i+-8i+24^2
= 6 - 26i +24*(-1)
= -18 - 26i
收錄日期: 2021-04-26 21:08:04
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