express the van der waals equation of state as a virial expansion in p

Question

Express the van der Waals equation of state as a virial expansion in powers of n/V, keeping terms up to the third power of (n/V). The result should have the form: \frac{p V}{n R T}=1+B \frac{n}{V}+C\left(\frac{n}{V}\right)^{2}+D\left(\frac{n}{V}\right)^{3}+\ldots Express the B, C, D virial coefficients in terms of the van der Waals parameters a and b. (don't include spaces in your answer; for powers, use ^). Use the Taylor-series expansion 1/(1-x) = 1 +x + x2 + ..., for |x|< 1. Hint: You may have seen something like this in class. Blank #1: B=? Blank #2: C=? Blank #3: D=?