\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(\Leftrightarrow x^3-27-3x+17=x^3-12\)

\(\Leftrightarrow-10-3x=-12\)

\(\Leftrightarrow3x=2\)

\(\Leftrightarrow x=\dfrac{2}{3}\)

Vậy...

\((x-3)(x^2+3x+9)-(3x-17)=x^3-12 \)

\(pt\Leftrightarrow x^3-27-3x+17=x^3-12\)

\(\Leftrightarrow x^3-3x-10-x^3+12=0\)

\(\Leftrightarrow2-3x=0\)\(\Leftrightarrow x=\dfrac{2}{3}\)

\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(\Rightarrow x\left(x^2+3x+9\right)-3\left(x^2+3x+9\right)-3x+17=x^3-12\)

\(\Rightarrow x^3+3x^2+9x-3x^2-9x-27-3x+17=x^3-12\)

\(\Rightarrow x^3+\left(3x^2-3x^2\right)+\left(9x-9x\right)-3x-10=x^3+12\)

\(\Rightarrow x^3-3x-10=x^3+12\)

\(\Rightarrow x^3-3x-10-12=x^3\)

\(\Rightarrow x^3-3x-22=x^3\)

\(\Rightarrow3x-22=0\)

\(\Rightarrow3x=22\Rightarrow x=\dfrac{22}{3}\)

23" role="presentation" style="border:0px; box-sizing:border-box; direction:ltr; display:inline; float:none; line-height:normal; margin:0px; max-height:none; max-width:none; min-height:0px; min-width:0px; padding:0px; position:relative; white-space:nowrap; word-spacing:normal; word-wrap:normal" class="MathJax">23

Vậy........

Nếu đúng thì k mk nha >.<

(x−3)(x2+3x+9)−(3x−17)=x^3−12

⇔x^3−27−3x+17−x^3+12=0

⇔2−3x=0

⇔3x=2⇒x=2/3

\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(\Leftrightarrow x^3-27-3x+17-x^3+12=0\)

\(\Leftrightarrow2-3x=0\)

\(\Leftrightarrow3x=2\Rightarrow x=\dfrac{2}{3}\)

\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(\Leftrightarrow x^3-27-3x+17-x^3+12=0\)

\(\Leftrightarrow-3x+2=0\)

\(\Rightarrow x=\dfrac{2}{3}\)

Vậy .............

\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(x^3-3^3-3x+17=x^3-12\)

\(-3x=-12+27-17=-2\)

=>\(x=\dfrac{2}{3}\)

Vậy...

ai nhanh nhất mk k cho nha ^^

23" role="presentation" style="border:0px; box-sizing:border-box; direction:ltr; display:inline; float:none; line-height:normal; margin:0px; max-height:none; max-width:none; min-height:0px; min-width:0px; padding:0px; position:relative; white-space:nowrap; word-spacing:normal; word-wrap:normal" class="MathJax">⇔3x=2⇒x=23

mk ko biet

\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)

\(x^3+3x^2+9x-3x^2-9x-37-3x+17=x^3-12\)

\(x^3+3x^2+9x-3x^2-9x-3x-x^3=37-17+12\)

\(-3x=32\)

\(x=\frac{32}{-3}=-\frac{32}{3}\)

Vậy x = \(-\frac{32}{3}\)

(x-3)(x\(^2\)+3x+9)-(3x-17)=x\(^3\)-12

(x\(^3\)-3\(^3\))-(3x-17)=x\(^3\)-12

3\(^3\)-3\(^3\)-3x+17=x\(^3\)-12

x\(^3\)-27-3x+17=x\(^3\)-12

x\(^3\)-27-3x+17-x\(^3\)=-12

-27-3x+17=-12

-27-3x=-29

3x=2

x=\(\frac{2}{3}\)

a) \(\dfrac{2}{3}x-\dfrac{1}{2}=\dfrac{1}{10}\)

\(\dfrac{2}{3}x=\dfrac{1}{10}+\dfrac{1}{2}=\dfrac{3}{5}\)

\(x=\dfrac{3}{5}:\dfrac{2}{3}=\dfrac{9}{10}\)

b) \(\dfrac{39}{7}:x=13\)

\(x=\dfrac{\dfrac{39}{7}}{13}=\dfrac{3}{7}\)

c) \(\left(\dfrac{14}{5}x-50\right):\dfrac{2}{3}=51\)

\(\dfrac{14}{5}x-50=51\cdot\dfrac{2}{3}=34\)

\(\dfrac{14}{5}x=34+50=84\)

\(x=\dfrac{84}{\dfrac{14}{5}}=30\)

d) \(\left(x+\dfrac{1}{2}\right)\left(\dfrac{2}{3}-2x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{2}=0\\\dfrac{2}{3}-2x=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)

e) \(\dfrac{2}{3}x-\dfrac{1}{2}x=\dfrac{5}{12}\)

\(\dfrac{1}{6}x=\dfrac{5}{12}\)

\(x=\dfrac{5}{12}:\dfrac{1}{6}=\dfrac{5}{2}\)

g) \(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\dfrac{11}{5}-\dfrac{3}{7}=-2\)

\(\left(x\cdot\dfrac{44}{7}+\dfrac{3}{7}\right)\cdot\dfrac{11}{5}=-2+\dfrac{3}{7}=-\dfrac{11}{7}\)

\(x\cdot\dfrac{44}{7}+\dfrac{3}{7}=-\dfrac{11}{7}:\dfrac{11}{5}=-\dfrac{5}{7}\)

\(\dfrac{44}{7}x=-\dfrac{5}{7}-\dfrac{3}{7}=-\dfrac{8}{7}\)

\(x=-\dfrac{8}{7}:\dfrac{44}{7}=-\dfrac{2}{11}\)

h) \(\dfrac{13}{4}x+\left(-\dfrac{7}{6}\right)x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x-\dfrac{5}{3}=\dfrac{5}{12}\)

\(\dfrac{25}{12}x=\dfrac{5}{12}+\dfrac{5}{3}=\dfrac{25}{12}\)

\(x=1\)

Mỏi tay woa bn làm nốt nha!!

17 - 2x = -15

2x = 17 - (-15)

2x = 32

x = 32 : 2

x = 16

--------

54 : (x + 2) = -6

x + 2 = 54 : (-6)

x + 2 = -9

x = -9 - 2

x = -11

--------

12.(3 - x) = 72

3 - x = 72 : 12

3 - x = 6

x = 3 - 6

x = -3

-------

-3(x + 5) + 18 = -27

-3(x + 5) = -27 - 18

-3(x + 5) = -45

x + 5 = -45 : (-3)

x + 5 = 15

x = 15 - 5

x = 10

-------

(x + 5)² = 9

x + 5 = 3 hoặc x + 5 = -3

*) x + 5 = 3

x = 3 - 5

x = -2

*) x + 5 = -3

x = -3 - 5

x = -8

Vậy x = -8; x = -2

--------

(3 - x)³ = 27

(3 - x)³ = 3³

3 - x = 3

x = 3 - 3

x = 0

=00

- 3\(x\) + 24  = -24

  3\(x\)          = 24 + 24

   3\(x\)          = 48

     \(x\)           = 48 : 3

     \(x\)           = 16

(x-3)(x² + 3x + 9) - (3x-17) = x(x² - 8)

<=> x³ - 27 - 3x + 17 = x³ - 8x

<=> 5x - 10 = 0

<=> 5x = 10

<=> x = 2

Vậy ...