IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IB => Math => Topic started by: candy on May 15, 2009, 04:34:52 pm

Title: MAth P3 A2 help.....
Post by: candy 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!
Title: Re: MAth P3 A2 help.....
Post by: naffy 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
Title: Re: MAth P3 A2 help.....
Post by: louis 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.

 
Title: Re: MAth P3 A2 help.....
Post by: candy on May 21, 2009, 07:43:29 pm
THANXXXXX ALOT louiss!!!  ;D ;D ;D ;D i really appreciate it!!!
Title: Re: MAth P3 A2 help.....
Post by: unfocused.. on July 21, 2009, 06:04:07 pm
any1 know where i cud get the may/june 2009 (paper 3)..?
Title: Re: MAth P3 A2 help.....
Post by: astarmathsandphysics on July 21, 2009, 07:22:03 pm
Not yet.