simplify −6(3i)(−2i) and 2(3 − i)(−2 + 4i) show work please

i^2 = -1

-6(3i) = -18i
-18i(-2i) = 36(i^2)
36(i^2) = 36(-1)
36(-1) = -36

i^2 = -1
2(3 - i)(-2 + 4i) :(do foil)
2(-6 + 12i +2i - 4i^2)
-2 (-6 + 14i +4)
-2(-2 + 14i)
4 -28i

4-28i is your answer

hope this helps

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godwinihagh godwinihagh · Answer 2 · 2020-01-13T12:47:21+01:00

Answer:

The answers are:

−6(3i)(−2i) = 36 × —1 = —36, and

2(3 – i)(−2 + 4i) = —4 + 28i

Step-by-step Explanations:

(i) −6(3i)(−2i) = —6 × 3i × —2i = —18i × —2i = 36i²

But we know that i² = —1

Therefore, −6(3i)(−2i) = 36 × —1 = —36

(ii) 2(3 – i)(−2 + 4i) = (6 — 2i)(—2 + 4i) = —12 + 24i + 4i — 8i² = —12 + 28i — 8i²

But i² = —1

Therefore, 2(3 – i)(−2 + 4i) = —12 + 28i — 8i² = —12 + 28i — 8 (—1) = —12 + 28i + 8 = —4 + 28i.