Originally Posted by

**ladythugette** hey, i'm finding it difficult how to factorise this equation:

t

³ - 3t² + 4 = 0 i've found out the answer already, but i really dont understand how i would get the answer- It would be very helpful if someone could give me a step to step guide on how to get to the answer. lolz..i've used the word answer so many times in this thread but i don't want to give it away incase some MHF users would like to solve the question themselves. Hi ladythugette,

You know, by the Rational zeros theorem, that if it has any rational roots at all,

they will be +/- the factors of 4.

I tried 2 and found that to be a zero, and used synthetic division to find the other two.

Code:

2 | 1 -3 0 4
2 -2 -4
---------------
1 -1 -2 0

The depressed polynominal is now a quadratic: $\displaystyle x^2-x-2$ and can easily be factored.