Purchase Solution

# Complex numbers

Not what you're looking for?

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

##### Solution Summary

This shows how to find roots of a polynomial and how to verify a trigonometric statement

##### 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 ...

##### Graphs and Functions

This quiz helps you easily identify a function and test your understanding of ranges, domains , function inverses and transformations.

##### Exponential Expressions

In this quiz, you will have a chance to practice basic terminology of exponential expressions and how to evaluate them.

##### Multiplying Complex Numbers

This is a short quiz to check your understanding of multiplication of complex numbers in rectangular form.