cath trial 2006 (1 Viewer)

[bboyelement]

http://www.angelfire.com/ab7/fourunit/cssa2006.pdf

i need help on 8a) part 3 and 4

 

[vafa]

Solution:

View attachment 13848

 

[Riviet]

A slight alternative to part iii):

(z⁵-1)/(z-1)=(z⁴+z³+z²+z+1)=(z²+...)(z²+...)

Don't expand and let z=1, take common factor of 2 from each bracket on RHS and you instantly get the required result.

 

[bboyelement]

thanks