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Express the following question in the form of a + bi. (3+5i)i (-2-7i)

1 Answer

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Answer: 31+29i

step 1) (3+5i)i
(3i+5i^2) i^2 = -1
(3i+ 5(-1) = (3i-5)

step 2 (FOIL) (3i-5)(-2-7i) = -6i-21i^2+10+35i

step 3) (simplify) (-6i+35i) +(-21i^2 +10) = (-6i+35i) +(21+10) = 31+29i
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