Mathematics: Post your doubts here!

usama321

usama321

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Suchal Riaz said:
that was supposed to give the correct answer. i don't know why it doesn't. maybe i need to check it. but i am not in mood.
and did you get it by my explanation or someone else explained it to you?
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Well Suchal, there are things called a bit complicated questions :p Not every question is easy. I had done this one before by using inverse, and did not get the right answer. I don't know the reason why it gives the wrong answer though
 
ZaqZainab

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Suchal Riaz said:
that was supposed to give the correct answer. i don't know why it doesn't. maybe i need to check it. but i am not in mood.
and did you get it by my explanation or someone else explained it to you?
Click to expand...
usama explained and thought blocker you were kinda late but i appreciate you helped
i was just trying to say its not simple even you thought it was f inverse the same happened with me
 
Thought blocker

Thought blocker

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386423 said:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_s09_qp_1.pdf
question 10
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10
i) 2(x^2-6x)+13
=2(x-3)^2+13
2(x^2-6x+9)+13
2x^2-12x+18 (-18+13=-5)
so 2(x-3)^2-5 ; a=2 b=-3 c=-5

ii) At x = 3 there is line of symmetry so A = x value so 1 is given zero and from 2(x-3)^2-5 we get A as 3 but we have 2 out the bracket hence A=6

iii) Range means all the values of y axes that graph covers, here , it is from xero to 13

iv) We have to show that it is one to one function so at x= 3 it is one to one, and 4 > 3 it has an inverse

v) Replace x by y and y by x
2(y-3)^2-5=x
make y the subject
we get y = ((root of x + 5)/2) + 3
replace y with f inverse sign and here is your answer. :)

Good luck :)
 
Suchal Riaz

Suchal Riaz

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ZaqZainab said:
usama explained and thought blocker you were kinda late but i appreciate you helped
i was just trying to say its not simple even you thought it was f inverse the same happened with me
Click to expand...
actually i didn't to the complete question. when i looked at f(x) in completed-sqaure form it suddenly struck to me how it has to be done. and believe me i have done this question. maybe in mocks. but as i didn't do complete question and i had to go for dinner at that time, i told you wrong answer.
 
Suchal Riaz

Suchal Riaz

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Thought blocker said:
I told you on fb!!! How was that ? o_O
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i want before 2009
and i did those questions wrong because i wasn't in mood of doing anything.
after question 3 my all questions are correct. and it was not a difficult paper.
a good paper is one from which you can learn something. where the examiner can trick you, even for a moment.
but P1 is all like find max point, find point of intersection find area under graph etc
i have been doing these kinds of questions for two years
 
Suchal Riaz

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believe me add math is harder than P1 and M1
and i have an A* in that.
i want hard questions to solve. i don't want to waste time in doing simple questions.
 
Thought blocker

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Suchal Riaz said:
i want before 2009
and i did those questions wrong because i wasn't in mood of doing anything.
after question 3 my all questions are correct. and it was not a difficult paper.
a good paper is one from which you can learn something. where the examiner can trick you, even for a moment.
but P1 is all like find max point, find point of intersection find area under graph etc
i have been doing these kinds of questions for two years
Click to expand...
Upload that solutions bro!
 
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