giddi77 wrote:

ccax is a math Guru and his Qs are definitely harder than GMAT Qs

ccax is there an easier way to solve this Q?

First of all giddi77, thanks for the flowers

I wish I could exchange the compliment into a decent GMAT score...

I don't think my questions are always harder than those of GMAT,

but I tried a few times to create a question that required to think

a bit different.

It's certainly true that you won't NEED 4th degree polynomials.

Because of that, I chose integers for the roots, so that the question

won't be too hard.

If you consider that a 4th degree polynomial can be represented as

(x-a)(x-b)(x-c)(x-d), where a, b, c and d are the roots, and you

expand this, then the only number independent from x is a*b*c*d,

which in our case was +8, representing the product of all roots of

the polynomial.

There aren't that many possibilites if all roots have to be integers,

so just try a few values. You won't need polynomial division in the

GMAT.

In calculating the roots of a polynomial, there are general formulas

for a polynomial up to 4th degree (that are exponentially growing

more complicate for 3rd and especially 4th degree). For polynomials

of a degree bigger than 4, there are only formulas for special cases.

As for the GMAT, you only need to bear in mind the formula for

x^2 + b x + c = 0.