Maths, Addmaths and Statistics: Post your doubts here!

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

In an equation when you add something, you have to subtract that too. So to complete the square we had to add the square of the half of the coefficient of x and to balance it, I subtracted it too.
It depends on the greater than or less than sign. If it is > then its positive but if x< ... then we use -ve sign.

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Yes I do get that... But after that I don't get that from where that -p came from????

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

Yes I do get that... But after that I don't get that from where that -p came from????

In the third step, he took the negative constant i.e. - (q/2p)^2 out of the bracket; the bracket which enclosed all terms that when taken out of it were being multiplied by p. So when one term was taken out,( the negative constant in our case) it had to be multiplied by p. (p cannot vanish on it's own, can it? :wink: )

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

For a moment I thought that but I got confused in the brackets... Silly Me! Thanks!

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

Your confusion was viable, Captain. I should've written that I multiplied the p with the -ve square but I thought you knew how to complete the square that is why I gave more attention to the inverse.

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Thats ok....

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

To get a better idea of completing the square open your D3 book and check the 2nd, 3rd and the 4th excercise of the first chapter.

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Nah... I do know that... There are many ways of doing it... Thanks anyway... I am done with O level... Waiting for the result...

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

Oh! Okay! Best of luck then.

 

[falcon678]

Re: O'level Maths, Addmaths and Statistics help available he

Salam everyone!!
wanted to ask that is only basic 3D locus comin in our examz????

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Walikum Salaam!

Are you done with the D4 Addendum Exercises?

 

[falcon678]

Re: O'level Maths, Addmaths and Statistics help available he

not all.....just locus's addendum exercise!

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Yeah just the Locus chapter... Then thats all... Practice locus questions from past papers...

 

[SalmanPakRocks]

Re: O'level Maths, Addmaths and Statistics help available he

Yeah just the Locus chapter... Then thats all... Practice locus questions from past papers...

Yeah there is a lot of difference between the book Language and past paper language

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Guess so...

 

[multixamza01]

Re: O'level Maths, Addmaths and Statistics help available he

can some one please help with Quadratic Inequalities in Add Math!

 

[CaptainDanger]

Re: O'level Maths, Addmaths and Statistics help available he

Check this : HERE

Post the question you are having problem in... There are many who can solve it for you...

 

[usman.1995]

Re: O'level Maths, Addmaths and Statistics help available he

I am facing in solving 2 Qs from past papers
Q1
paper 12 ....oct nov 2010 ....Q5.(i).(c)...unable to understand hoe 34 answer comes as mentioned in the examiner report of this paper

Q2
paper 13.....oct nov 2010.....Q6 (ii).....don't know how to prove it

Someone plz explain ......THANKS

 

[OakMoon!]

Re: O'level Maths, Addmaths and Statistics help available he

I assume the subject is Statistics.

Q1. Since, there are no guys who can get A or B after the grade D is predicted as stated by i)b, the total number of candidates with the predicted grade "D" can either get a "C" or a "D". C has a 1/3 chance, so D will have a 2/3 chance. Using this information find the total number of candidates (X) with the predicted grade of "D". (2/3)*X=68, hence, X=102. To find those who got a "C" just take the one third of 108 and you'll get 34.

 

[abcde]

Re: O'level Maths, Addmaths and Statistics help available he

^Exactly! usman.1995 asked the same question in a separate thread and he may want to check the answer there as well.