# Write Complex Number in Standard Form

Discussion in 'Other Pre-University Math' started by nycmathguy, Sep 14, 2021.

1. ### nycmathguy

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Section 2.4
14, 18, 20

Question 14

4 + sqrt{-49}

4 + sqrt{49} • sqrt{-1}

4 + 7 • sqrt{-1}

Let sqrt{-1} = I

4 + 7i

Question 18

50 becomes 50 + 0i.

Question 20

-2i^2 + 4i

Let i^2 = -1

-2(-1) + 4i

2 + 4i

You say?

Can you do 22?

nycmathguy, Sep 14, 2021
2. ### MathLover1

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22.
sqrt(-0.025)
sqrt(0.025)sqrt(-1)
0.158114i

MathLover1, Sep 14, 2021
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3. ### nycmathguy

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There's a typo here. You forgot one extra 0 in the radicand.

nycmathguy, Sep 14, 2021
4. ### MathLover1

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sorry, ty for paying attention to it

sqrt(0.0025)sqrt(-1)
sqrt(25/10000)sqrt(-1)
sqrt(5^2)/sqrt(100^2))*i
(5/100)*i
0.05i

Last edited: Sep 14, 2021
MathLover1, Sep 14, 2021
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5. ### nycmathguy

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One thing I love about math is the attention to details it requires.

nycmathguy, Sep 15, 2021
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6. ### MathLover1

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yes, math is all about the facts and the attention to details

MathLover1, Sep 15, 2021
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