Đáp án:
`a, x=-2,x=8`
`b, x=(19)/3`
Giải thích các bước giải:
`a,(x-8)(x³+8)=0`
`<=>`\(\left[ \begin{array}{l}x-8=0\\x³+8=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=8\\x³=-8\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=8\\x³=(-2)^³\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}x=8\\x=-2\end{array} \right.\)
Vậy `x=-2, x=8`
_________________
`b, (4x-3)-(x+5)=3.(10-x)`
`<=> 4x -3 -x -5 =30-3x`
`<=> 3x -8 =30-3x`
`<=> 3x +3x =30+8`
`<=> 6x =38`
`<=> x= (19)/3`
Vậy `x=(19)/3`
