Mathematics: Post your doubts here!

[talhajohar]

q6

 

[saimaiftikhar92]

in question number 1 i tried alot! to do but still the answer is not coming correct......so i wanted to know where i am going wrong

 

[talhajohar]

have you used the graphical method?

 

[saimaiftikhar92]

no

 

[talhajohar]

try that because it never gets wrong. squaring both sides and then solving fails in some questions.

 

[talhajohar]

P1 o/n 08 Q 9 (ii) and (iii) and Q10

 

[saimaiftikhar92]

i got the graphical method of solving inequalities

 

[saimaiftikhar92]

talhajohar.......in your reply to jason .......in functions question , (iii) part , second last line the value should be -9 not -18

right?

 

[talhajohar]

yeah you are right.

 

[saimaiftikhar92]

koi baat nahi

 

[floral123]

there is a question that
find equivalent values of x equivalent to trignometric ratios given
sin(-260) ??
answers are 80 and 100.
i got 80 as -260 is in 2nd quadrant moving clockwise so formula will be -180-(-260)=80
but cant find 100 how???
plz help...


also cos(-200) and cos(-30)??
i would be grateful if someone explains clockwise movement in trignometry.

 

[saimaiftikhar92]

the best way to do this is to remeber that sin is negative in the third and fourth quadrant. make two seperate diagrams for this

 

[hassam]

w09 p31

 

[abcde]

w09 p31

AoA!
(i) to find the vector equation of the line MN, you require the position vector of a point on the line, say OM and the direction vector MN.
AB = OB - OA = 2i + 2j - 2k
AM = 1/2 AB = i + j - k
This allows you to calculate OM.
OM = OA + AM = 2i + j - 2k

AC = OC - OA = 3i - 3j + 3k
AN = 2 NC ===> AN = 2/3 AC
=> AN = 2i - j + k
MN = AN - AM = i - 2j + 2k
So the vector equation of MN is r = 2i + j - 2k + s(i - 2j + 2k), where s is any parameter.

(ii) The vector equation of BC would be r = 3i + 2j - 3k + t(i - 5j + 5k)
Equate the two equations. Find out the values of the parameters, s & t. Inserting the found values into any equation will give you the position vector of P.

 

[hassam]

thanks

 

[abcde]

No hay problema, sir!

 

[saimaiftikhar92]

http://www.xtremepapers.com/CIE/index.p ... _qp_31.pdf


i need help in question no 4

 

[abcde]

http://www.xtremepapers.com/CIE/index.php?dir=International%20A%20And%20AS%20Level/9709%20-%20Mathematics/&file=9709_s10_qp_31.pdf


i need help in question no 2 ,3 and 4

You've asked q3 before and it had been replied to then. :S Take a look again: viewtopic.php?f=26&t=10916&start=660

 

[saimaiftikhar92]

ohh sorry!

 

[saimaiftikhar92]

i need help only in question number 4