IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => Subject Doubts => IGCSE/ GCSE => Math => Topic started by: ~~~~shreyapril~~~~ on October 20, 2009, 03:11:59 pm
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i have this question please answer it Astar math or slvri i need help
Please help wid diagram if possible..
Points A and B have position vectors a and b respectively relative to the origin O. The point C lies on OA produced such that OC = 2OA, and d lies on OB such that OD = 1/3OB
i) Express BC and DA in terms of a and b
The lines AD and BC intersect at P when extended
ii) Given that AP = mDA, express OP in terms of m, a, b
iii) Given also that BP = kBC, express OP in terms of k, a, b
iv) Hence calculate the value of m and k and the position vector of p
v) Another point Q is such that APCQ is a parallelogram. Find its position vector.
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here
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tks sir
i did not get the step in the attachment
how come QC = AP
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i guess 2a - (3a - b) = b-a
rite?? or not??
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Because QCAP is a paralellogram. It goes APQC so AP is antiparalle to QC so paralell to CQ. I should have crawn it on. Sorry.
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i guess 2a - (3a - b) = b-a
rite?? or not??
yes my mistake
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k thanx sir got it...
i will come back if i have some more doubts
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refer to the diagram..
1) BC = 2a - b
DA = -b/3 + a
2) OP = OA + AP
OP = a(1+m) -mb/3
3) OP = OB + BP
OP = b + 2ak - bk
4) 2k = 1 + m
1 - k = -m/3
solve them
m =3
k=2
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first find QC = AP = 3a - b
therefore, CQ = b-3a
OQ = OC + CQ
= 2a + b - 3a = b-a
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go it mannn
thanx.
by the way what name did you give to the image??
dhan tana!!!
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AM I will have to learn to do images as good as that.
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AM I will have to learn to do images as good as that.
sir, its nuthing complicated..use MS paint..
thats it!
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i thought you used photoshop cause i heard u pretty well in it
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At themoment i only use openoffice. I dont have much ms software.
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ohh
y dont u use a torrent and download it
By the way i guess paint is by default in every pc i guess
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I will get ms office
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u not having ms office so wat u use mac or something else cause i think u cant work without ms office
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u not having ms office so wat u use mac or something else cause i think u cant work without ms office
sir uses open office. thats what he said
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arre hahahaha
frgt
really :-[ :-[ :-[