Question

已知1+2+3+...+n=m.求代数式(a^n乘b)(a^n-1乘b^2)(a^n-2乘b^3)…(ab^n)的值

Answer 1

(a^n乘b)(a^n-1乘b^2)(a^n-2乘b^3)…(ab^n)

=[a^(n+n-1+n-2+...+1)]*b^(1+2+3+...+n)

=[a^m]*b^m

=(ab)^m