1. For each of the following, simplify so that the variable term is raised is to a single power: (a) State the General Term tr in the Binomial expansion of (2x^2 - 1/x)^10 (b) Find the 7th term in the expansion (c) Is there an x^5 term? Find its coefficient. (d) Is there a constant term [independent of x] ? Find it if there is? this is what i have so far... a) tr = C(10,r) (2x^2)^(10-r)*(-1/x)^r = C(10,r) 2^(10-r) * x^(20-r)* (-1)^r * x^-r = 2^(10-r) * (-1)^r * C(10,r) * x^(20-3r) b) Since it is t7, r = 6 so t7 = 2^4 * (-1)^6 * C(10,6) * x^2 = 3360x^2 c) Let 20-3r = 5, so r = 5. So t5 = 2^5 * (-1)^5 * C(10,5) * x^2 and the coefficient is -8064 d) Let 20-3r = 0 r = 20/3 so there is no constant term? a somewhat unrelated topic, but another quesiton... 2. http://img161.imageshack.us/img161/4540/explicit9uq.jpg [Broken] how can i utilize the hints to develop a formula?