Author Topic: MAth P3 A2 help.....  (Read 2611 times)

Offline candy

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MAth P3 A2 help.....
« on: May 15, 2009, 04:34:52 pm »
The complex number
2/-1 +i  is denoted by u.



(i) Find the modulus and argument of u and u^2. [6]



(ii) Sketch an Argand diagram showing the points representing the complex numbers u and u^2. Shade
the region whose points represent the complex numbers z which satisfy both the inequalities |z|<2
and |z-u^2| < |z-u|. [4]



please can someone answer part 2 for me!!! i dont understand!!  ??? :'( :'(

its a question from may june 2007...i checked the markscheme but i don tunderstand it at all...can someone draw it n show it pllzzz...Thanks a lot!

Offline naffy

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Re: MAth P3 A2 help.....
« Reply #1 on: May 16, 2009, 02:33:43 am »
IzI<2 is a circle at origin with radius 2

and then substitute the value of u and u^2 at both side.it should be a perpendicular bisector between both if i'm not mistaken

Offline louis

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Re: MAth P3 A2 help.....
« Reply #2 on: May 18, 2009, 12:52:34 pm »
Candy,
For l Z l <2, you have to draw a circle of radius 2. But the circumference line must be dotted and it means   the radius is not equal to 2 but less than 2.

From point U ( -1,-1) to U² (0, 2),join these two points. Draw a perpendicular bisector of this line
until it meets the circle at 2 points,namely  Z  and  Z1.
Finally, shade the area of the sector Z U2 Z1. Plz refer to the attachment.

 

Offline candy

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Re: MAth P3 A2 help.....
« Reply #3 on: May 21, 2009, 07:43:29 pm »
THANXXXXX ALOT louiss!!!  ;D ;D ;D ;D i really appreciate it!!!

Offline unfocused..

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Re: MAth P3 A2 help.....
« Reply #4 on: July 21, 2009, 06:04:07 pm »
any1 know where i cud get the may/june 2009 (paper 3)..?

Offline astarmathsandphysics

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Re: MAth P3 A2 help.....
« Reply #5 on: July 21, 2009, 07:22:03 pm »
Not yet.