Please help me answer both of these questions. Thank you :)

Printable View

- June 15th 2006, 10:03 PMnoriveaComplex numbers
Please help me answer both of these questions. Thank you :)

- June 15th 2006, 11:47 PMCaptainBlackQuote:

Originally Posted by**norivea**

This has three roots, one real corresponding to the first factor; so is a root.

The other two roots are the roots of the second factor , these may

be found using the quadratic formula, which gives in this case:

RonL - June 16th 2006, 12:39 AMCaptainBlackQuote:

Originally Posted by**norivea**

given that is a root.

A cubic with real coefficients always has at least one real root, and

complex roots occur in conjugate pairs. So both and

are roots. Also:

where is real, and so easily found to be ,

so the remaining root is .

RonL