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denpristay [2]
3 years ago
8

Multiply 3i(−1 + 2i). What is the simplified version written in standard form, a + bi, where a and b are real numbers?

Mathematics
1 answer:
Sholpan [36]3 years ago
4 0
3i (- 1 + 2i)     Remove the brackets.
3i (-1) + (2i)(3i) Look at the first set of brackets around the -1
-3i + 6i^2     But i^2 = - 1[ I hope that's the way you are using it]
-3i - 6 or -6 - 3i or -3(2 - i) <<<<< answer
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Some people think it is unlucky if the 13th day of a month falls on a Friday. Show that in every calendar year (non leap or leap
MakcuM [25]
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5 0
3 years ago
If the radius of a circle is 4 1/4 feet, what is the diameter
iragen [17]
All i know is that if the radius of a circle is 4 feet, the the diameter is 8 feet. Sorry, I don't know the rest.
4 0
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masya89 [10]
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the answer is 2. see attached for step-by-step instructions. hope that helps!

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