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Find the product and fill in the blanks to write in standard complex number form.

Find the product and fill in the blanks to write in standard complex number form.-example-1
User Sigurdb
by
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2 Answers

4 votes

Answer:

26 + 22i

Explanation:

Given

(2 + 4i)(7 - 3i) ← expand product using FOIL

= 14 - 6i + 28i - 12i² ← i² = - 1

= 14 + 22i + 12

= 26 + 22i ← in standard form

User Suppen
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5.4k points
1 vote

For this case we must simplify the following expression:


(2 + 4i) (7-3i)

We apply distributive property considering that:


+ * - = -\\- * - = +\\2 * 7 + 2 * (- 3i) + (4i) * 7- (4i) (3i) =\\14-6i + 28i-12i ^ 2 =

We take into account that:


i ^ 2 = -1

So:


14-6i + 28i-12 (-1) =\\14-6i + 28i + 12 =

Adding similar terms:


14 + 12 + 28i-6i =\\26 + 22i

Answer:


26 + 22i

User Pedro Ghilardi
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5.9k points