You are Here: Home >< Maths

# FP2 Complex Number Transformations Watch

1. I'm struggling with the following FP2 Q6 from Jun 09.
A Transformation T from the z-plane to the w-plane is given by w=z/z+i.
The circle with equation (mod z)=3 s mapped by T onto the curve C
Show that the curve is a circle and give it's radius.
I have found z in terms of w. But have a term which is wi and I'm not sure how to put that into Cartesian form. I have tried wi=ui-v but that has given me a slightly incorrect answer.
Help would be greatly appreciated =)
2. (Original post by EduinJBL)
I'm struggling with the following FP2 Q6 from Jun 09.
A Transformation T from the z-plane to the w-plane is given by w=z/z+i.
The circle with equation (mod z)=3 s mapped by T onto the curve C
Show that the curve is a circle and give it's radius.
I have found z in terms of w. But have a term which is wi and I'm not sure how to put that into Cartesian form. I have tried wi=ui-v but that has given me a slightly incorrect answer.
Help would be greatly appreciated =)
rearrange to get z in terms of w like you have already done, then use to get 3 in terms of w, then multiply out the bottom and use

Edit: that's the bit you needed isn't it, sorry I forgot that
because
3. Thanks alot, that makes perfect sense and gives me the correct answer.

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: April 3, 2013
Today on TSR

### Anxious about my Oxford offer

What should I do?

### US couple arrested - 13 children chained up

Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• ## See more of what you like on The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

• The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE