Originally Posted by

**egshih** Hi All,

I got this problem and it seems like it should be straight forward, but I get the wrong answer. I listed below my reasoning. What is wrong with what I am doing? Any help would be greatly appreciated.

Let B={$\displaystyle 2x^3-5x^2+3x+7,x^2-4x+9,1/2x+5,3$}

Find <$\displaystyle 3x^3+6x^2-8x+27$> by method of comparing coefficients.

Here is what I did.

<$\displaystyle 3x^3+6x^2-8x+2$> =C1<$\displaystyle 2x^3-5x^2+3x+7$> +C2<$\displaystyle x^2-4x+9$> +C3<$\displaystyle 1/2x+5$>+C4*3

2C1=3, C1=3/2

C2-5=6 C2= 11

1/2C3-4+3= -8

1/2C3=-7

C3=-14

3C4+9+7+5=27

3C4=6

C4=2

<3/2,11, -14,2>