1. The coefficient of x6y4 in the expansion of (2x-y)10 is ?
2. An arithmetic sequence has a=15 and the common difference d=-3/2. Find the value of 10 over Sigma k=5 ak = the kth term of the sequence.
3. Find the 3rd term in the expansion of (x+6)10.
Sequences and Expansions are analyzed to find terms and coefficients