General Discussions

Page 10 of 10   •  First Page  •  Previous Page  •   Next Page  •   Last Page
Signup or Login to Post
POLL: A simple mathematical problerm
  • Current rank: 3.5 Stars. Next Rank at 8000 Posts.
    Send a message to forty-two
    AUTHOR
    forty-two posted on Apr 28, 2011 4:19:09 PM - Report post
     
    quote:
    originally posted by Neo7

    Back to this again.

    I asked my mathematics professor (Ph.D. in mathematics). He says the answer is 288 becaues the divisor of the division problem is always the length of one real number unless specificed by a sub-equation completely encased in parenthesis/brackets (with the open parenthesis/bracket occuring immediately after the division symbol).

    48/2(3+9) = 288
    48/[2(3+9)] = 2

    So what does 48/i2 come out to? 24i or -24i? I know that it's improper to write the i first, but we've clearly thrown syntax out the window.

    /--\
  • Current rank: 4 Stars. Next Rank at 10.000 Posts.
    Send a message to Neo7
    AUTHOR
    Neo7 posted on Apr 28, 2011 5:42:16 PM - Report post
     
    Rewrite the i as Math.Sqrt(-1) and rationalise the denominator. It will return negative.

    1. 48/(2i)
    2. (48i)/(2 * -1)
    3. (48i) / (-2)
    4. -24i
    Your bitterness, I will dispel
  • Current rank: 3.5 Stars. Next Rank at 8000 Posts.
    Send a message to forty-two
    AUTHOR
    forty-two posted on Apr 28, 2011 5:44:15 PM - Report post
     
    quote:
    originally posted by Neo7

    Rewrite the i as Math.Sqrt(-1) and rationalise the denominator. It will return negative.

    1. 48/(2i)
    2. (48i)/(2 * -1)
    3. (48i) / (-2)
    4. -24i

    But like you said, "the divisor of the division problem is always the length of one real number". So it should be 48/2 * i. Right?

    /--\
  • Current rank: 4 Stars. Next Rank at 10.000 Posts.
    Send a message to Neo7
    AUTHOR
    Neo7 posted on Apr 28, 2011 6:15:38 PM - Report post
     
    A complex number is written in the form a + bi.

    2i is a complex number (not a real number) [Represented fully as 0+2i]
    Your bitterness, I will dispel
  • Current rank: 1 Star. Next Rank at 100 Posts.
    Send a message to Paper_Masochist
    ELITE
    Paper_Masochist posted on May 01, 2011 10:59:06 AM - Report post
     
    quote:
    originally posted by Neo7

    Back to this again.

    I asked my mathematics professor (Ph.D. in mathematics). He says the answer is 288 becaues the divisor of the division problem is always the length of one real number unless specificed by a sub-equation completely encased in parenthesis/brackets (with the open parenthesis/bracket occuring immediately after the division symbol).

    48/2(3+9) = 288
    48/[2(3+9)] = 2

    X(Y+Z) is shorthand for ((X x Y)+(X x Z)) it's called expanding the brackets.

    So 48/2(3+9) = 2.

    You can't say these are just algebra rules applied to standard math because the convention of assuming multiplication when there's no symbol specifically comes from algebra (2a is 2 x a)

  • Current rank: 4 Stars. Next Rank at 10.000 Posts.
    Send a message to Neo7
    AUTHOR
    Neo7 posted on May 01, 2011 12:14:26 PM - Report post
     
    quote:
    originally posted by Paper_Masochist

    quote:
    originally posted by Neo7

    Back to this again.

    I asked my mathematics professor (Ph.D. in mathematics). He says the answer is 288 becaues the divisor of the division problem is always the length of one real number unless specificed by a sub-equation completely encased in parenthesis/brackets (with the open parenthesis/bracket occuring immediately after the division symbol).

    48/2(3+9) = 288
    48/[2(3+9)] = 2

    X(Y+Z) is shorthand for ((X x Y)+(X x Z)) it's called expanding the brackets.

    So 48/2(3+9) = 2.

    You can't say these are just algebra rules applied to standard math because the convention of assuming multiplication when there's no symbol specifically comes from algebra (2a is 2 x a)

    The way it's written, it would be (48/2)(3+9) for the distributive property. 48/2 is the monomial for the 3+9 part.

    Your bitterness, I will dispel
  • Current rank: 1 Star. Next Rank at 100 Posts.
    Send a message to Paper_Masochist
    ELITE
    Paper_Masochist posted on May 01, 2011 12:42:27 PM - Report post
     
    quote:
    originally posted by Neo7

    quote:
    originally posted by Paper_Masochist

    quote:
    originally posted by Neo7

    Back to this again.

    I asked my mathematics professor (Ph.D. in mathematics). He says the answer is 288 becaues the divisor of the division problem is always the length of one real number unless specificed by a sub-equation completely encased in parenthesis/brackets (with the open parenthesis/bracket occuring immediately after the division symbol).

    48/2(3+9) = 288
    48/[2(3+9)] = 2

    X(Y+Z) is shorthand for ((X x Y)+(X x Z)) it's called expanding the brackets.

    So 48/2(3+9) = 2.

    You can't say these are just algebra rules applied to standard math because the convention of assuming multiplication when there's no symbol specifically comes from algebra (2a is 2 x a)

    The way it's written, it would be (48/2)(3+9) for the distributive property. 48/2 is the monomial for the 3+9 part.

    So if it was written like this: 48/a(3+9) = x

    You would instantly try to expand 48/a in 3 and 9? Once again this must go back into the way we were taught in certain countries because I aced expanded maths and that definitely looks like 2 is the multiplier to me.



    Edit: Hmmm I can see how you're right too, it's so confusing because all mathematics I've done recently has been formatted entirely differently. I see it as:

    48
    --
    2(3+4)

    And the alternative as:

    48
    -- x (3+4)
    2

    [Edited by Paper_Masochist, 5/1/2011 12:50:24 PM]

Page 10 of 10   •  First Page  •  Previous Page  •   Next Page  •   Last Page
Signup or Login to Post
All times are (GMT -06:00) Central Time (US & Canada). Current time is 7:56:18 AM