Help with polynomials roots question (1 Viewer)

[sarkar_as]

I've done c i and ii but for iii is there a faster way to solve the equation than just expanding the whole thing?

I've looked at the answers and they show a faster method but I don't understand it.

Thanks.

 

[si2136]

Unless you remember the formula, not that I know of.

 

[InteGrand]

I've done c i and ii but for iii is there a faster way to solve the equation than just expanding the whole thing?

I've looked at the answers and they show a faster method but I don't understand it.

Thanks.View attachment 33600View attachment 33601

They got their first set of three equations from the fact that alpha, beta, gamma are roots.

They got the next equation by adding those three equations and rearranging. This allowed the previous results to be utilised.