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The product of two complex numbers 1 + i and 2 − 5i is

1. 7 − 3i
2. 3 − 4i
3. −3 − 4i
4. 7 + 3i

Correct answer: 7 − 3i

Solution

To find the product of the complex numbers 1 + i and 2 - 5i, we use the distributive property (FOIL method), which results in 1*2 + 1*(-5i) + i*2 + i*(-5i). This simplifies to 2 - 5i + 2i + 5, combining like terms gives 7 - 3i.

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