计算 (1-1⼀2^2)(1-1⼀3^2)…(1-1⼀9^2)(1-1⼀10^2)

计算 (1-1/2^2)(1-1/3^2)…(1-1/9^2)(1-1/10^2)
2024-12-30 17:12:14
推荐回答(2个)
回答1:

=(1-1/2)(1+1/2)(1-1/3)(1+1/3)(1-1/4)(1+1/4)...(1-1/9)(1+1/9)(1-1/10)(1+1/10)
=(1/2)(3/2)(2/3)(4/3)(3/4)(5/4)...(8/9)(10/9)(9/10)(11/10)
=(1/2)(11/10)
=11/10
运用平方差公式分解!

回答2:

=(1-1/2)(1+1/2)(1-1/3)(1+1/3)(1-1/4)(1+1/4)...(1-1/9)(1+1/9)(1-1/10)(1+1/10)
=(1/2)(3/2)(2/3)(4/3)(3/4)(5/4)...(8/9)(10/9)(9/10)(11/10)
=(1/2)(11/10)
=11/20