Đáp án-Giải thích các bước giải:
`c)` `(3x - 2^4).7^37=2.7^38`
`⇒` `(3x -16).7^37=2.7.7^37`
`⇒` `3x - 16 = 2.7`
`⇒` `3x - 16 = 14`
`⇒` `3x = 14 + 16`
`⇒` `x = 30`
`⇒` `x = 30 : 3`
`⇒` `x = 10`
`Vậy` `:` `x=10`
`d)` `720 : [45-(5-2x)^3]=(2^3).5`
`⇒` `720 : [45-(5-2x)^3]=8.5`
`⇒` `720 : [45-(5-2x)^3]=40`
`⇒` `45-(5-2x)^3 = 720 : 40`
`⇒` `45-(5-2x)^3 = 18`
`⇒` `(5-2x)^3 = 45 - 18`
`⇒` `(5-2x)^3 = 27`
`⇒` `(5-2x)^3 = 3^3`
`⇒` ` 5-2x = 3`
`⇒` `2x = 5-3=2`
`⇒` `x = 1`
`Vậy` `:` `x = 1`
`e)` `(4x-1)^3 = 27^2`
`⇒` `(4x-1)^3 = 9^3`ư
`⇒` `4x-1 = 9`
`⇒` `4x = 9+1 = 10`
`⇒` `x = 10 : 4 = 5/2`
`Vậy` `:` `x=5/2`
`#` `Dũng``v``v`
XIN CTLHN !
