# Math Help - Binomial Coefficients Help

1. ## Binomial Coefficients Help

Hi, can anyone run me through the process of answering this question and explain each step to me.

Find the coefficient of x^2 in the expression (x^2-3/x)^7

Thanks.

2. You have been given the solution.
http://www.mathhelpforum.com/math-he...html#post80091

3. That $\frac{3}{x}$ part... Is that part of the $x$ value or $y$ value?

4. Originally Posted by janvdl
That $\frac{3}{x}$ part... Is that part of the $x$ value or $y$ value?
$\left( {a + b} \right)^7 ,\quad \left( {x^2 - \frac{3}{x}} \right)^7 , \Rightarrow a = x^2 \;\& \;b = - \frac{3}{x}$