Maths can be weird....
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http://www.sgforums.com/?action=thread_display&thread_id=139668&page=5Originally posted by monkeybusiness:where is tat?
although the forum itself is quite dead -
Neither do I currently.Originally posted by hisoka:yeah lor, but the maths so weird to me, i don't get all the maths questions correct
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i almost neverOriginally posted by hisoka:yeah lor, but the maths so weird to me, i don't get all the maths questions correct -
thats why maths is weird and doesn't make sense. it should let me get all the questions right and easily oneOriginally posted by CoolMyth:Neither do I currently. -
practise more bahOriginally posted by hisoka:yeah lor, but the maths so weird to me, i don't get all the maths questions correct 
last time in pri n sec sch, i oso hate maths alot
but den in poly, i suddenly love dem -
practice also no use. you practice every second of the day you also won't get all right. and thats not easily leOriginally posted by monkeybusiness:practise more bah
last time in pri n sec sch, i oso hate maths alot
but den in poly, i suddenly love dem 
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nxt time i buy 4D or toto, can coolmyth calculate the probability of me striking first prize?
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Well, I'm past that level lor.Originally posted by monkeybusiness:practise more bah
last time in pri n sec sch, i oso hate maths alot
but den in poly, i suddenly love dem
Can you believe some of my maths 90% words? -
50/50 lah. Any kid can tell you.Originally posted by monkeybusiness:nxt time i buy 4D or toto, can coolmyth calculate the probability of me striking first prize?
Either you tio or you dun. -
got 1 method sure effective and u wun get tiredOriginally posted by hisoka:practice also no use. you practice every second of the day you also won't get all right. and thats not easily le
everyday count $$ den plot graph -
probability one of my stronger topics last timeOriginally posted by monkeybusiness:nxt time i buy 4D or toto, can coolmyth calculate the probability of me striking first prize?
but for 4D it is like 1/alotofdigits
now can't remember anything, brain taking a break from maths...forever
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source-based type of maths questionsOriginally posted by CoolMyth:Well, I'm past that level lor.
Can you believe some of my maths 90% words? -
thats not effective. and it doesn't always work too. he can not strike for all his life and hte probability may also not be zeroOriginally posted by monkeybusiness:got 1 method sure effective and u wun get tired
everyday count $$ den plot graph -
i dun really like probabilityOriginally posted by finoq:probability one of my stronger topics last time
but for 4D it is like 1/alotofdigits
now can't remember anything, brain taking a break from maths...forever
and i oso dun like vectors
some of the topics i like are integration, differentiation, logarithm, trigonometrics, L'Hopital rule, Laplace, fourier series
although i hav forgotten some of them -
you actually like laplace and fourier??Originally posted by monkeybusiness:i dun really like probability
and i oso dun like vectors
some of the topics i like are integration, differentiation, logarithm, trigonometrics, L'Hopital rule, Laplace, fourier series
although i hav forgotten some of them 
next time i got to do some hard fourier transform i can ask you le -
tis is called the "Sine wave".Originally posted by hisoka:thats not effective. and it doesn't always work too. he can not strike for all his life and hte probability may also not be zero
there are ups and downs -
Ok let me give you a proof to this question but i am not sure whether i am correct or not.Originally posted by finoq:The logic of 1÷0 = error
Suppose not. That is 1 / 0 is not equal to error. Meaning 1 / 0 is equal to 'x' where x is any real (or even complex) number.
Rearranging 1/0=x,
we get x*0=1.
But if we take x*0, we will get 0. (We know that any numbers, be it real or complex when times 0 to it will yields 0.
Therefore contradiction, x cannot take any real (or complex) number. -
its been some time since i last do these qnsOriginally posted by hisoka:you actually like laplace and fourier??
next time i got to do some hard fourier transform i can ask you le
but i can always try -
actually its just undefined cos if you approach 1/0 from 2 different directions, you will get different valuesOriginally posted by Gasfene:Ok let me give you a proof to this question but i am not sure whether i am correct or not.
Suppose not. That is 1 / 0 is not equal to error. Meaning 1 / 0 is equal to 'x' where x is any real (or even complex) number.
Rearranging 1/0=x,
we get x*0=1.
But if we take x*0, we will get 0. (We know that any numbers, be it real or complex when times 0 to it will yields 0.
Therefore contradiction, x cannot take any real (or complex) number. -
I am showing why it is undefined.Originally posted by hisoka:actually its just undefined cos if you approach 1/0 from 2 different directions, you will get different values
Draw the graph of y=1/|x|. you approach from 2 different directions, you still get the same limits. -
Both you and hisoka also correct.Originally posted by Gasfene:I am showing why it is undefined.
Depending on what type of proof are you asking for. Mathematical logically or calculus in hisoka's way.
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As long as got one counterexample, can already. Example 1/x.Originally posted by Gasfene:I am showing why it is undefined.
Draw the graph of y=1/|x|. you approach from 2 different directions, you still get the same limits. -
The question is trying to prove that 1/0 = error ALWAYS. You need to show for all cases. Anyway, that counter example didnt show anything to teach you why 1/0 =error.
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actually its undefined not error.Originally posted by Gasfene:The question is trying to prove that 1/0 = error ALWAYS. You need to show for all cases. Anyway, that counter example didnt show anything to teach you why 1/0 =error.
and its undefined as long as there is such an example -
Yep.Originally posted by hisoka:actually its undefined not error.
and its undefined as long as there is such an example
The idea is the same. You can't have two possible values for y for x = 0. The logic method and the calculus are similar in that sense.