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colormekaylee
08-01-2009, 11:42 AM
A polynomial x has a degree 3.
The coefficent of x^2 is 3 less than the coefficent of x^3
The coefficent of x is three times the coefficent of x^2.
The remaning coefficent is 2 more than x^3.
The sum of all the coefficents is -4
Find the polynomial.

Help!?

galactus
08-01-2009, 12:37 PM
Write out your general cubic.

ax^{3}+bx^{2}+cx+d=0

Now, let a be the base to work from.

It says the coefficient of x^2 is 3 less than the coefficient of x^3. The coefficient of x^3 is a, so the coefficient of x^2, b, is a-3. b=a-3

Go ahead and set them up using the clues. It should all be in terms of a, so set equal to -4 and solve for a. The others will fall into place.