1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算

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1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算1.345×0.345×

1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算
1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算

1.345×0.345×2.69—1.345^2-1.345×0.345^2×2简便计算
方法一:
1.345×0.345×2.69—1.345^2-1.345×0.345^2×2
=(1+0.345)×0.345×2.69—1.345²-0.345²×2.69
=0.345×2.69 + 0.345²×2.69—1.345²—0.345²×2.69
=0.345×2.69—1.345²
=0.345×1.345×2—1.345²
=1.345×(0.345×2-1.345)
=1.345×(-0.655)
= -0.880975
方法二:
令 a=1.345
1.345×0.345×2.69—1.345^2-1.345×0.345^2×2
=a×(a-1)×2a-a²-(a-1)²×2a
=2a²(a-1)-a²-2a(a-1)²
=2a(a-1)(a-a+1)-a²
=2a²-2a-a²
=a²-2a
=a(a-2)
=1.345×(1.345-2)
=1.345×(-0.655)
= -0.880975

请再仔细检查,中间肯定有错误之处!!!