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Simplify (10 + 3i)(5 − 2i).

A.) 50 − 5i − 6i2
B.) 44 − 5i
C.) 56 − 5i
D.) 50 − 6i2

User Septi
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2 Answers

2 votes
The answer I think is D but use the app photo math very useful:)
User Giorgos Betsos
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4 votes

Answer: The correct option is

(C) 56-5i.

Step-by-step explanation: We are given to simplify the following product of complex numbers :


P=(10+3i)(5-2i)~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)

To simplify the given product, we must multiply each term of the first factor each term of the second factor and will be using the following vale of i :


i=√(-1)~~~~\Rightarrow i^2=-1.

From (i), we get


P\\\\=(10+3i)(5-2i)\\\\=10(5-2i)+3i(5-2i)\\\\=50-20i+15i-6i^2\\\\=50-5i-6(-1)\\\\=50-5i+6\\\\=56-5i.

Thus, the required simplified form is 56-5i.

Option (C) is CORRECT.

User David Bendahan
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