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Please somebody help me out!!

Please somebody help me out!!-example-1

1 Answer

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Answer:

See below.

Explanation:

These work just like ordinary algebraic expresssions, except you have to remember always: i^2 = -1 i squared is negative one!

(4 - 3i)(4 + 3i) "FOIL" the expression to get 16 - 3i + 3i - 9i^2. But i^2 = -1, so this is the same as 16 - 3i + 3i + 9. Combine like terms.

Ans. 25

(4 - 3i)(i) Distribute the i to the two terms of the binomial.

4i - 3i^2 = 4i - 3(-1)

Ans. 4i + 3

(6i)(4 + 3i) = (6i)(4) + (6i)(3i) = 24i + 18i^2 = 24i + 18(-1)

Ans. 24i -18

(6i)(i) = 6i^2 = 6(-1)

Ans. -6

(-5)(4 + 3i) = -20 - 15i That's it; there's no i^2 to deal with.

Ans. -20 - 15i

(-5)(i) = -5i Again, that's all there is to it.

Ans. -5i

User Thiago Lewin
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