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问题: 1+7/1)(1+7/2)(1+7/3)---(1+7/9)/(1+9/1)(1+9/2)(1+9/3)---(1+9/7)=(

解答:

[(1+7/1)(1+7/2)(1+7/3)---(1+7/9)]/(1+9/1)(1+9/2)(1+9/3)---(1+9/7)
=[(8/1)×(9/2)×(10/3)×……×(16/9)]/[(10/1)×(11/2)×(12/3)×……×(16/7)]
=[(8×9×10×11×12×13×14×15×16)/(1×2×3×4×5×6×7×8×9)]/[(10×11×12×13×14×15×16)/(1×2×3×4×5×6×7)]
=(8×9)/(8×9)
=1。