1. One root Z3-15z2+76z-140 = 0 is an integer. Solve the equation.
5. The eqution Z4-8z3+20z2-72z+99= 0 has a pure imaginary root Solve the equation.
Please give me some tip on what i should do !!
Thanks a lot!
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- Thread Starter
- 26-03-2016 23:35
- Official Rep
- 29-03-2016 01:50
Sorry you've not had any responses about this.
Why not try posting in a specific subject forum- you might have more luck there.
Here's a link to our subject forum which should help get you more responses.
- 29-03-2016 01:51
- 29-03-2016 02:32
For the second one, try relating the coefficients to the roots. Then use the fact that there is a purely imaginary root, and the fact that all of the coefficients are real to manipulate the 4 equations you get and you can find all 4 roots this way.
(I had to have a go at this question myself as once the factor formula couldn't find any roots I couldn't not solve it could I?)
Answers: Don't cheatLast edited by B_9710; 29-03-2016 at 02:39.