Complex numbers
1. The equation X^5 - 2X^4 - X^3 + 6X - 4 = 0 has a repeated root at X=1 and a root at X-2. By a process of division and solving a quadratic equation, find all the roots and hence write down all the factors of X^5 - 2X^4 - X^3 + 6X - 4
2. Given that cosX= (e^jx + e^-jx)/2
sinX= (e^jx - e^-jx)/2j
using only this information, prove that 2cos5xsin2x = sin7x-sin3x
Any help is would be greatly appreciated
© BrainMass Inc. brainmass.com March 4, 2021, 5:59 pm ad1c9bdddfhttps://brainmass.com/math/number-theory/complex-numbers-questions-22309
Solution Preview
Please find the solutions in the attached file.
Solution to posting # 22309
1. Given equation: X5 - 2X4 - X3+ 6X - 4 = 0
Also given that (x-1) and (x-2) are solutions of the above equation. Performing long ...
Solution Summary
This shows how to find roots of a polynomial and how to verify a trigonometric statement
$2.19