Đáp án:
Giải thích các bước giải:
`(x + 3)(x^2 – 3x + 9) – x(5+ x^2) = 52`
`<=>x^3+27−x(5+x^2)=52`
`<=>x^3+27−(5x+x^3)=52`
`<=>x^3+27−5x−x^3=52`
`<=>27−5x=52`
`<=>−5x=52−27`
`<=>−5x=25`
`<=>x=\frac{25}{-5}=-5`
Vậy `x=-5`
`4x(5 – x) + ( x – 1)(4x–3 )=3 `
`<=>20x−4x^2+4x^2−7x+3=3`
`<=>20x−7x+3=3`
`<=>13x+3=3`
`<=>13x=3−3=0`
`<=>x=0`
Vậy `x=0`
`2x(x + 2) - (2x + 3)(x – 1) = 4`
`<=>2x^2+4x−(2x^2+x−3)=4`
`<=>2x^2+4x−2x^2−x+3=4`
`<=>4x−x+3=4`
`<=>3x+3=4`
`<=>3x=4−3=1`
`<=>x=\frac{1}{3}`
Vậy `x=\frac{1}{3}`
`4x(x – 5) – ( x – 1)(4x – 3 ) = 3`
`<=>4x^2−20x−(4x^2−7x+3)=3`
`<=>4x^2−20x−4x^2+7x−3=3`
`<=>−20x+7x−3=3`
`<=>−13x−3=3`
`<=>−13x=3+3=6`
`<=>x=\frac{6}{-13}`
Vậy `x=-\frac{6}{13}`
