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Qualification => Subject Doubts => IGCSE/ GCSE => Math => Topic started by: Q80BOY on May 06, 2009, 01:33:30 pm

Title: Math P2 Oct/Nov 2000 HELP !!!
Post by: Q80BOY on May 06, 2009, 01:33:30 pm

IGCSE (CIE) Mathematics October/November 2000

(ive attached the paper)

Page 4, Question 10 (Done)

Page 10, Question 22, Part (c) (Done)

Special thanks to DE, Astarmathsandphysics and Aishath

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: MissDE on May 06, 2009, 01:45:16 pm

See, X>= 4.8

so  the answer might be {1,2,3,4}

not sure thu..

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: Q80BOY on May 06, 2009, 01:46:45 pm

Quote from: DE on May 06, 2009, 01:45:16 pm

See, X>= 4.8

so  the answer might be {1,2,3,4}

not sure thu..

Thanks for the help, but how did we get 4.8 ??

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: astarmathsandphysics on May 06, 2009, 01:47:54 pm

Quote from: Q80BOY on May 06, 2009, 01:33:30 pm

IGCSE (CIE) Mathematics October/November 2000

(ive attached the paper)

Page 4, Question 10

Page 10, Question 22, Part (c)

Total number of questions: 2

I really hope u guys can help me out !!!  ;D

10)7 – 5x> – 17
 7+17>5x
5x<24 so x<4.8
22c)f(g(x))=3-2g(x)=3-2(x+1)/4=(12-2x-2)/4=(5-x)/2

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: MissDE on May 06, 2009, 01:50:32 pm

7-5x>= -17

-5x>=-17-7

-5x>= -24

divide by 5 and turn the sign (as u divide by nigative)...

Got it??

Feel free to ask if u don't understand..

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: Q80BOY on May 06, 2009, 02:07:41 pm

Thanks for ur help DE and Astar, i appreciate it !!  ;D

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: Aishath on May 06, 2009, 02:18:58 pm

for ques.22 (c)

fg(x) means u hv to put g function in f.
f(x)=3 – 2x
g(x)=(x+1)/4

so wherever x is in f(x), put g(x) values in it.

f(x)=3 - 2x ya?
f(x)=3 - 2((x+1)/4)           (the bold one from top is put into x in f(X))
f(x)=3 - ((2x + 2)/4)            
then simplify (2x + 2)/4
which is       (x + 1)/2

then f(x)=3 - (x + 1)/2
            =6/2 - (x + 1)/2
therefore=(6 - x + 1)/2
            =(7 - x)/2
so thats the ans!!!!

fg(x)=(7 - x)/2

hope u got it ;)

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: sanity_master on May 06, 2009, 02:20:29 pm

i guess im LATE :D lol

i hope i catch it nxt time :):D

Title: Re: Math P2 Oct/Nov 2000 HELP !!!
Post by: Q80BOY on May 06, 2009, 02:28:24 pm

Quote from: sanity_master on May 06, 2009, 02:20:29 pm

i guess im LATE :D lol

i hope i catch it nxt time :):D

i will save a question for u next time  ;)