A-Level Further Maths B7-02 Argand Diagram: Examples of Circles |z-a|=r

[nosir]

Why do we change the sign of the -a in |z-a| or vice versa? Might seem like a basic question but I've always tried figuring out why change it and I always found it hard to make sense of it?

[vedangikulkarni]

Hi, i always had this confusion, in the first question, do we have to measure out the 9 units while drawing the circle? Is it supposed to be on scale? Or do we just draw a normal circle and label it as 9 units like you did? Thanks

[evyvaleria]

Hi, firstly thankyou so much for your videos! when we're labelling the numbers on the imaginary axis, for example question 1 had a radius of 9. How come the labels aren't -9i and 9i? or is it essentially 9 + 0i which is why we write just 9?

[adonayghirmay]

Why the circle doesnt touch the origin in number 4? Plzzzz tell me how.

[satriario]

why is the radius in the 1st question is 9?

[henryaustin]

Do you know how you would sketch a locus that had Z* instead of Z inside the modulus? This question came up in my exam and I wasn't sure how to sketch it. Many thanks

[samuellarbi]

Please i don't get question 6 why does it go through the centre?

[ME-ctmr]

How do you know where to draw the circle