Tính nhanh: 34 + 35 : 86 + 65 x 75 + 65 x 45
Tìm x: a, (2 x * + 1)^3 =125
b, (7 x * – 11)^3 =2^5 : 2^2 + 200
Tính nhanh: 34 + 35 : 86 + 65 x 75 + 65 x 45 Tìm x: a, (2 x * + 1)^3 =125 b, (7 x * – 11)^3 =2^5 : 2^2 + 200
By Kinsley
By Kinsley
Tính nhanh: 34 + 35 : 86 + 65 x 75 + 65 x 45
Tìm x: a, (2 x * + 1)^3 =125
b, (7 x * – 11)^3 =2^5 : 2^2 + 200
`35 × 34 + 35 × 86 + 65 × 75 + 65 × 45`
`= 1190 + 35 × 86 + 65 × 75 + 65 × 45`
`= 1190 + 3010 + 65 × 75 + 65 × 45`
`= 1190 + 3010 + 4875 + 65 × 45`
`= 1190 + 3010 + 4875 + 2925`
`= 12000`
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a, `(2x+1)^3=125`
`(2x+1)^3=5^5`
`2x+1=5`
`2x=4`
`x=2`