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I need help with 2 math problems. Complex Numbers
1. Which expression is equal to (8−3i)−(6+i)?

14−4i
2−4i
2−2i
14−2i

2. Multiply.

(5+2i)(4−3i)

Enter your answer, in standard form, in the box.

Respuesta :

You add, subtract and multiply complex numbers exactly as you do with variables: you sum like terms, recalling that [tex]i^2=-1[/tex]

So, you have

[tex](8-3i)-(6+i) = 8-3i-6-i = 8-6-3i-i = 2-4i [/tex]

And

[tex] (5+2i)(4-3i) = 20-15i+8i-6i^2 = 20-7i+6 = 26-7i [/tex]