有详细步骤不要直接给答案 计算(1)(0.027)^-1⼀3-(-1⼀7)^-2+(2又7⼀9)^1⼀2-(√2-1)^0

(2)(1/4)^-1/2×(√4ab^-1)^3/0.1^-2(a^3b^-3)^1/2
2024-12-20 21:29:30
推荐回答(3个)
回答1:

(1)(0.027)^-1/3-(-1/7)^-2+(2又7/9)^1/2-(√2-1)^0
=[(0.3)³]^(-1/3)-1/(-1/7)²+√(25/9)-1
=0.3^(-1)-49+5/3-1
=1/0.3-49+5/3-1
=10/3+5/3-50
=5-50
=-45
注意(-1/7)^-2=1/(-1/7)²=1/(1/49)=49
(2)(1/4)^-1/2×(√4ab^-1)^3/0.1^-2(a^3b^-3)^1/2
=[2^(-2)]^(-1/2)×2³a^(3/2)b^(-3/2)/[10^(-1)](-2)a^(3/2)b^(-3/2)
=2×2³a^(3/2-3/2)b^(-3/2+3/2)/10²
=(16/100)a^0b^0
=4/25
注意√b^(-1)=b^(-1/2)

回答2:

只帮你做一个:
(1)(0.027)^-1/3-(-1/7)^-2+(2又7/9)^1/2-(√2-1)^0
=(0.3^3)^-1/3 - 1/49 + (25/9)^1/2 - 1
=0.3^-1 - 1/49 + 5/3 -1
=10/3+5/3-1-1/49
=5-1-1/49
=3又48/49 (YAO)

回答3:

(1)(0.027)^-1/3-(-1/7)^-2+(2又7/9)^1/2-(√2-1)^0=10/3-49+5/3-1=-45
2)(1/4)^-1/2×(√4ab^-1)^3/0.1^-2(a^3b^-3)^1/2=2*(8*a^3/2*b^-3/2)/100(a^3/2b^-3/2)=4/25