Midpoint in the Complex Plane

Discussion in 'Geometry and Trigonometry' started by nycmathguy, Feb 16, 2022.

  1. nycmathguy

    nycmathguy

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    Section 6.5

    Can you do 46 as a guide for me to do the rest on my days off? Thank you.

    Screenshot_20220215-093606_Samsung Notes.jpg
     
    nycmathguy, Feb 16, 2022
    #1
  2. nycmathguy

    MathLover1

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    46.
    -3+4i
    1-2i

    The midpoint of the line segment joining two complex numbers a + bi and s + ti is the
    average of the numbers at the endpoints.

    Midpoint Formula in the Complex Plane is:

    Midpoint = (a + s)/2+ ((b + t)/2 )i

    -3+4i=a + bi => a=-3, b=4
    1-2i= s + ti =>s=1, t=-2

    Midpoint = (-3 + 1)/2+ ((4 -2)/2 )i=-1+i
     
    MathLover1, Feb 16, 2022
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  3. nycmathguy

    nycmathguy

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    I will do the rest this weekend. Thanks..
     
    nycmathguy, Feb 16, 2022
    #3
  4. nycmathguy

    nycmathguy

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    IMG_20220218_163522.jpg
     
    nycmathguy, Feb 18, 2022
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  5. nycmathguy

    MathLover1

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    correct
     
    MathLover1, Feb 18, 2022
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  6. nycmathguy

    Country Boy

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    NO! Given the points, \(-1+ \frac{3}{4}i\) and
     
    Country Boy, Feb 19, 2022
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  7. nycmathguy

    Country Boy

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    First, you write the general formula as "[(a+ s)/2+ (b+ t)/2]i" which is incorrect. It should be (a+ s)/2+ [(b+ t)/2]i.

    Also, didn't you say that these "points in the complex plane" are to be written as "a+ bi", NOT as "(a, b)"? The midpoint of the line segment in the complex plane with endpoints -1- (3/4)i and 1/2+ (1/4)i is -1/4- (1/4)i, not "(-1/4, -1/4)".
     
    Country Boy, Feb 19, 2022
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  8. nycmathguy

    nycmathguy

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    Thanks.
     
    nycmathguy, Feb 19, 2022
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  9. nycmathguy

    MathLover1

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    he was using right formula
    upload_2022-2-19_10-56-22.jpeg

    btw, you say
    "he write the general formula as "[(a+ s)/2+ (b+ t)/2]i" which is incorrect. It should be (a+ s)/2+ [(b+ t)/2]i."
    what is the difference between your formula and his formula?
     
    MathLover1, Feb 19, 2022
    #9
  10. nycmathguy

    Country Boy

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    2+ 3i is NOT the same as [2+ 3]i= 5i.
     
    Country Boy, Feb 19, 2022
    #10
  11. nycmathguy

    MathLover1

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    what is your point?
     
    MathLover1, Feb 19, 2022
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  12. nycmathguy

    Country Boy

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    You asked "What is the difference between your formula and his formula?

    My point was to answer that question!
    His formula was "[(a+ s)/2+ (b+ t)/2]i" which is incorrect. My formula was "(a+ s)/2+ [(b+ t)/2]i." Notice the "[ ]" in his formula- everything inside [ ] is multiplied by i.

    In my formula the [ ] surrounds only the '(b+ t)/2' and only that is multiplied by i.


    i
     
    Country Boy, Feb 20, 2022
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  13. nycmathguy

    nycmathguy

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    I found the posted formula online. It did not come out of my ass.
     
    nycmathguy, Feb 21, 2022
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  14. nycmathguy

    Country Boy

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    Well, wherever it came from, it is still wrong. A complex number has two parts, a "real part" and an "imaginary part". Only the "imaginary part" is multiplied by i.

    Either it was wrong on the internet or you copied it incorrectly.
     
    Country Boy, Feb 22, 2022
    #14
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