QuangDai234
`3, 3^x = 9^10`
`=> 3^x = 3^20`
`=> x = 20`
Vậy `x = 20`
`6, (1/5)^x = (1/125)^3`
`=> (1/5)^x = (1/5)^9`
`=> x = 9`
Vây `x = 9`
`9, (3/5)^x = (9/25)^3`
`=> (3/5)^x = (3/5)^9`
`=> x = 9`
Vậy `x = 9`
`12, 2^(3 - 2x) = 8^3`
`=> 2^(3 - 2x) = 2^9`
`=> 3 - 2x = 9`
`=> 2x = -6`
`=> x = -3`
Vậy `x = -3`
`15, 2^(3x + 1) = 32^2`
`=> 2^(3x + 1) = 2^10`
`=> 3x + 1 = 10`
`=> 3x = 9`
`=> x = 9 : 3 = 3`
Vậy `x = 3`
`18, 3^(6 - 3x) = 81^3`
`=> 3^(6 - 3x) = (3^4)^3`
`=> 3^(6 - 3x) = 3^12`
`=> 6 - 3x = 12`
`=> 3x = -6`
`=> x = -2`
Vậy `x = -2`
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