anyone good at emaths?

• pandemona

  2 Oct 07, 14:55

  as above and willing to trade msn cause i have quite alot question to ask...thanks PM me please
  and im not a clone...lol just needed some help
• Darkness_hacker99

  2 Oct 07, 14:56

  You can post your questions here too.
• wishboy

  2 Oct 07, 15:20

  mi
  however only up to sec 3
  although i must say i screwed my emaths paper 2 today the teacher trying to kill ppl, set until so difficult
• HyuugaNeji

  2 Oct 07, 15:34

  me good
• eagle

  2 Oct 07, 15:52

  I'm lousy.
• newcomer

  2 Oct 07, 18:08

  how does distinction sound to u?
• pandemona

  2 Oct 07, 19:37

  me taking o level bah...so i need mentor lor
  anyone want to trade msn? can pm me
• cApitaland

  2 Oct 07, 19:44

  post your questions here.
  
  there are more than enough qualified people here from both poly and jc.
  
  sadly i got only a2.
• euc

  2 Oct 07, 19:46

  Got few maths experts around.
• pandemona

  2 Oct 07, 19:52

  Factorisation
  a) 4x²-12x+9=0
  b) 2x²=7x
• lpx88

  2 Oct 07, 19:55

  Originally posted by pandemona:

  Factorisation
  a) 4x²-12x+9=0
  b) 2x²=7x

  a)4x²-12x+9 =0
  = (2x-3)(2x-3) =0
  2x-3=0
  2x=3
  x=1.5
  
  b)2x²=7x
  2x²-7x=0
  x(2x-7) =0
  x =0 or 2x-7 =0
  2x=7
  x=3.5
  
  x=0 or 3.5
• eagle

  2 Oct 07, 20:45

  Originally posted by euc:

  Got few maths experts around.

  but not me
• euc

  2 Oct 07, 20:47

  Originally posted by eagle:

  but not me

  pat pat
  
  I know...
• CoolMyth

  2 Oct 07, 20:48

  I 2nd lower. Can help?
• dbowie

  2 Oct 07, 20:49

  Originally posted by pandemona:

  Factorisation
  a) 4x²-12x+9=0
  b) 2x²=7x

  a)(2x-3)(2x-3)=0
  x=3/2
  
  b)2x^2-7x=0
  x(2x-7)=0
  x=0 or 3.5
  
  
• eagle

  2 Oct 07, 20:50

  Originally posted by euc:

  pat pat
  
  I know...

  
  I promise to improve my maths
• popikachu

  2 Oct 07, 21:33

  I am good at O lvl e mathematics. ^^
• pandemona

  2 Oct 07, 23:16

  wow got so many sexperts around..if i got more question i post here lor
• unclebutcher

  2 Oct 07, 23:19

  i got a1.
• pandemona

  3 Oct 07, 14:40

  can someone teach me how to do completing the square?
  
  example: 2x²+7x-3=0
  
  and : 2x=5 - 1/x
• eagle

  3 Oct 07, 17:04

  Originally posted by pandemona:

  can someone teach me how to do completing the square?
  
  example: 2x²+7x-3=0
  
  and : 2x=5 - 1/x

  2x²+7x-3=0
  2(x²+3.5x) -3 =0
  2(x²+3.5x+[3.5/2]²) - 2[3.5/2]² -3 = 0
  2(x+3.5/2)² - 9.125 = 0
  
  Usually as a quick way of checking such questions whether you did correctly, what you do is to sub in values for 1 side to check.
  
  ie
  if x=0, 2x²+7x-3 = -3
  if x=0, 2(x+3.5/2)² - 9.125 = -3
  
  u can try for x=1 to further confirm
  If same, then confirm correct. No need to recheck question at all. Save your time for other stuff
  
  Part 2
  multiply x throughout
  2x² = 5x - 1
  2x² - 5x + 1 = 0
  
  From here try yourself first following my above steps
• HyuugaNeji

  3 Oct 07, 17:43

  2(x+3.5/2)² - 9.125 = 0
  

  2(x+3.5/2)²=9.125
  (x+3.5/2)²=4.5625
  (x+3.5/2)=+2.316 or -2.316
  x=0.386 or -4.066
• eagle

  3 Oct 07, 17:45

  Originally posted by HyuugaNeji:

  2(x+3.5/2)²=9.125
  (x+3.5/2)²=4.5625
  (x+3.5/2)=+2.316 or -2.316
  x=0.386 or -4.066

  
  I let him try first one leh
  
• pandemona

  3 Oct 07, 20:39

  i dont quite understand how u get this part
  2(x²+3.5x+[3.5/2]²) - 2[3.5/2]² -3 = 0
  
  how u get - 2[3.5/2]²
• eagle

  3 Oct 07, 20:40

  Originally posted by pandemona:

  i dont quite understand how u get this part
  2(x²+3.5x+[3.5/2]²) - 2[3.5/2]² -3 = 0
  
  how u get - 2[3.5/2]²

  inside I add
  so outside I subtract
  
  so in the end add zero, which does not affect the equation at all