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CaHeK987 [17]
3 years ago
8

Multiply and simplify the following complex numbers: (1 + 2i) x (1 - 4i)

Mathematics
1 answer:
Ivanshal [37]3 years ago
6 0

Answer:

9-2i

Step-by-step explanation:

(1 + 2i) * (1 - 4i)

(1*1)-(1*4i)+(2i*1)-(2i)*(4i)

(1)-(4i)+(2i)-(8i^2)

i^2 = -1

1-4i+2i+8

1-2i+8

9-2i

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