O-Level Additional Math

[nounou]

deleted

[nounou]

Hi, need help on another Q. Kindly help. Thank you.


Evaluate 2012^2 - 2011^2 + 2010^2 - 2009^2 + ...
+ 4^2 - 3^2 + 2^2 - 1^2

:? :?:

:thankyou:

[koguma]

deleted

[koguma]

nounou:

Hi, need help on another Q. Kindly help. Thank you.


Evaluate (2012^2 - 2011^2) + (2010^2 - 2009^2) + ...
+ (4^2 - 3^2) + (2^2 - 1^2)

:? :?:

:thankyou:

Use this formulae : a^2 − b^2 = (a + b)(a − b)

2012^2 - 2011^2
= (2012+2011)(2012-2011)
= 2012+2011

2010^2 - 2009^2
= (2010+2009)(2010-2009)
= 2010+2009

4^2 - 3^2
= (4+3)(4-3)
= 4+3

2^2 - 1^2
= (2+1)(2-1)
= (2+1)

so you need to add 1+2+3+4 .... +2009+2010+2011+2012 to get the ans.

hopefully someone else can give a shorter working answer.

[nounou]

deleted

[nounou]

Hi, thank you very much for your help. I understand your workings.


Q: how to find 1+2+3+4 .... +2009+2010+2011+2012 ???? :?:

Please help. :thankyou: :lovesite:

koguma:

nounou:

Hi, need help on another Q. Kindly help. Thank you.

Evaluate (2012^2 - 2011^2) + (2010^2 - 2009^2) + ...
+ (4^2 - 3^2) + (2^2 - 1^2)

:? :?:

:thankyou:

Use this formulae : a^2 − b^2 = (a + b)(a − b)

2012^2 - 2011^2
= (2012+2011)(2012-2011)
= 2012+2011

2010^2 - 2009^2
= (2010+2009)(2010-2009)
= 2010+2009

4^2 - 3^2
= (4+3)(4-3)
= 4+3

2^2 - 1^2
= (2+1)(2-1)
= (2+1)

so you need to add 1+2+3+4 .... +2009+2010+2011+2012 to get the ans.

hopefully someone else can give a shorter working answer.

[Jtutor]

Hi nounou,


To solve for 1+2+3+…+2010+2011+2012, you can group them together as follow:
(1+2012)+(2+2011)+(3+2010)+…
There will be a total of 2012/2=1006 pairs.
Hence 1006 x 2013 = 2,025,078.

Hope it helps.

Cheers,
Jtutor

[nounou]

:thankyou: :udaman: :lovesite:

Jtutor:

Hi nounou,

To solve for 1+2+3+..............+2010+2011+2012, you can group them together as follow:
(1+2012)+(2+2011)+(3+2010)+...
There will be a total of 2012/2=1006 pairs.
Hence 1006 x 2013 = 2,025,078.

Hope it helps.

Cheers,
Jtutor

[Yamong]

Can anyone recommend physics tution arround bukit timah?

[htn]

Hi


Please help.

Secondary Two Maths.

Factorise

1)2r^2-5r-3

Expand and simplify the following expressions
1)(a+b)^2 - (a-b)^2

2)(x+2y)(x-6y)- (x-3y)(x-y)

TIA