IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: cashem'up on October 26, 2010, 02:22:42 pm
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Hey guys i really need some help in maths regarding this question A levl exam tmrow w05 qp3 q7 last part regarding argand diagram Thanks
Sketch an Argand diagram showing the point representing the complex number 1 + 2i. Show on
the same diagram the set of points representing the complex numbers which satisfy
|z| = |z ? 1 ? 2i| .
How do u do this please please help
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ONe moment.
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Sorry to let you down but I cant solve this. I'm doing further maths but still.... its out of my depth.
Sorry dude !
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damn!!!....aghh...hey man can u try again... xam tomorow a level....please please... By the way where is astar....god help me
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Hey guys i really need some help in maths regarding this question A levl exam tmrow w05 qp3 q7 last part regarding argand diagram Thanks
Sketch an Argand diagram showing the point representing the complex number 1 + 2i. Show on
the same diagram the set of points representing the complex numbers which satisfy
|z| = |z ? 1 ? 2i| .
How do u do this please please help
okay, so you replace 'z' with 'x+iy', so you have |x+iy|=|x+iy-1-2i|
-> x^2 + y^2 = (x-1)^2 + (y-2)^2
-> x^2 + y^2 = x^2 -2x +1 + y^2 -4y +4
-> 2x+4y = 5 ---- you can leave it like this and draw the line of this equation, or simplify it further (which is what I like to do) and you get: y= (5/4) - (1/2)x
Just draw this line and you're done
Hope this helped :)
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Hey guys i really need some help in maths regarding this question A levl exam tmrow w05 qp3 q7 last part regarding argand diagram Thanks
Sketch an Argand diagram showing the point representing the complex number 1 + 2i. Show on
the same diagram the set of points representing the complex numbers which satisfy
|z| = |z ? 1 ? 2i| .
How do u do this please please help
Here's another method :
[ z ] = [ z - 1 - 2i ]
=> [ z - (0 + 0i)] = [ z - (1 + 2i)]
It represents the line which bisects perpendicularly the line joining (0,0) and (1,2).
So you just need to plot the points (0,0i) and (1,2i) on your Argand diagram and the bisect the line joining them.
Hope it's clear enough for you to understand ;)
By the way I have p3 as well tomorrow :D
Try to relax a bit and do not get stressed out especially when the paper comes in front of you ;)
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Here's another method :
[ z ] = [ z - 1 - 2i ]
=> [ z - (0 + 0i)] = [ z - (1 + 2i)]
It represents the line which bisects perpendicularly the line joining (0,0) and (1,2).
So you just need to plot the points (0,0i) and (1,2i) on your Argand diagram and the bisect the line joining them.
Hope it's clear enough for you to understand ;)
By the way I have p3 as well tomorrow :D
Try to relax a bit and do not get stressed out especially when the paper comes in front of you ;)
How did you find the paper? I found it really easy, except for the last part of the vectors question! Hopefully shouldn't be losing more than 4-5 marks overall.
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How did you find the paper? I found it really easy, except for the last part of the vectors question! Hopefully shouldn't be losing more than 4-5 marks overall.
Same for me.
It was a very easy paper. However I was not able to complete the number for vectors part 3. :(
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Same for me.
It was a very easy paper. However I was not able to complete the number for vectors part 3. :(
Wow, same here lol. Vectors part c was the only question I couldn't finish correctly. Fingers crossed that I got everything else right! Do you remember any of your answers?
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Wow, same here lol. Vectors part c was the only question I couldn't finish correctly. Fingers crossed that I got everything else right! Do you remember any of your answers?
Hmm.........some of them, yeah!
You wanna compare answers ?
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haha....even i am a bit late but yes exactly only the vectors last part confused me....damn i got something 2x + ?y+ ?Z= -14 , dont remember any more and in vectors part 2 by chance did u get some fractions
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haha....even i am a bit late but yes exactly only the vectors last part confused me....damn i got something 2x + ?y+ ?Z= -14 , dont remember any more and in vectors part 2 by chance did u get some fractions
Hmm........for the last part my friends got it equal to 26.
Yeah the second part was ( 2/3 , 5/3 , 7/3 )
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Lol welcome back cashem'up
Yeah, I got the same answer (2/3, 5/3, 7/3) for vectors part two! Thank God you guys also found part 3 difficult. I think I got the equation for plane AOB, but then I couldn't work out how to find the plane perpendicular to IT. Hopefully they'll give me one or two marks for that lol.
Was your last differential equation answer, 'tends towards 20' or something like that?
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Lol welcome back cashem'up
Yeah, I got the same answer (2/3, 5/3, 7/3) for vectors part two! Thank God you guys also found part 3 difficult. I think I got the equation for plane AOB, but then I couldn't work out how to find the plane perpendicular to IT. Hopefully they'll give me one or two marks for that lol.
Was your last differential equation answer, 'tends towards 20' or something like that?
Yeah........i did the same thing for the vectors.............but i don't think that will be adequate to score marks :-\
Yupz............last one tend to 20!
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Yeah........i did the same thing for the vectors.............but i don't think that will be adequate to score marks :-\
Yupz............last one tend to 20!
heyy, the ppr wasnt that bad...but i just want to know your solutions to the differential question like what did you get the 2nd and 3rd parts?? like the general solution, i remember that there was some ln(20) or somethin like that.. :-\
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heyy, the ppr wasnt that bad...but i just want to know your solutions to the differential question like what did you get the 2nd and 3rd parts?? like the general solution, i remember that there was some ln(20) or somethin like that.. :-\
I can't remember it exactly but my answer sure included ln 20. ;)