Question 6
Calculate $\binom81+9\binom82+9^2\binom83+\cdots+9^6\binom87+9^7\binom88$.
HKIMO 2017 THPT (Grades 10–12 shared) National Final (Heat) Set 04 Question 6
HKIMO · HKIMO 2017 THPT (Grades 10–12 shared) National Final (Heat) Set 04
HKIMO · HKIMO 2017 THPT (Grades 10–12 shared) National Final (Heat) Set 04