(x-3)(x^2+3x+9)-(3x-17)=x^3-12
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Leftrightarrow x^3-27-3x+17=x^3-12\)
\(\Leftrightarrow-10-3x=-12\)
\(\Leftrightarrow3x=2\)
\(\Leftrightarrow x=\dfrac{2}{3}\)
Vậy...
\((x-3)(x^2+3x+9)-(3x-17)=x^3-12 \)
\(pt\Leftrightarrow x^3-27-3x+17=x^3-12\)
\(\Leftrightarrow x^3-3x-10-x^3+12=0\)
\(\Leftrightarrow2-3x=0\)\(\Leftrightarrow x=\dfrac{2}{3}\)
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Rightarrow x\left(x^2+3x+9\right)-3\left(x^2+3x+9\right)-3x+17=x^3-12\)
\(\Rightarrow x^3+3x^2+9x-3x^2-9x-27-3x+17=x^3-12\)
\(\Rightarrow x^3+\left(3x^2-3x^2\right)+\left(9x-9x\right)-3x-10=x^3+12\)
\(\Rightarrow x^3-3x-10=x^3+12\)
\(\Rightarrow x^3-3x-10-12=x^3\)
\(\Rightarrow x^3-3x-22=x^3\)
\(\Rightarrow3x-22=0\)
\(\Rightarrow3x=22\Rightarrow x=\dfrac{22}{3}\)
Tìm x biết:
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Leftrightarrow x^3-27-3x+17-x^3+12=0\)
\(\Leftrightarrow2-3x=0\)
\(\Leftrightarrow3x=2\Rightarrow x=\dfrac{2}{3}\)
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(\Leftrightarrow x^3-27-3x+17-x^3+12=0\)
\(\Leftrightarrow-3x+2=0\)
\(\Rightarrow x=\dfrac{2}{3}\)
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...
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
223" 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=22⇒x=223
(x−3)(x^2+3x+9)−(3x−17)=x^3−12
⇔x^3−27−3x+17=x^3−12
⇔−10−3x=−12
⇔3x=2
⇔x=2/3
Vậy...
Tìm x biết:
(x-3)(x^2+3x+9)-(3x-17)=x^3-12
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
Tìm x biết:
(x - 3).(x2 + 3x +9) - (3x - 17) = x3 - 12
\(\left(x-3\right)\left(x^2+3x+9\right)-\left(3x-17\right)=x^3-12\)
\(x^3+3x^2+9x-3x^2-9x-37-3x+17=x^3-12\)
\(x^3+3x^2+9x-3x^2-9x-3x-x^3=37-17+12\)
\(-3x=32\)
\(x=\frac{32}{-3}=-\frac{32}{3}\)
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. 2/3x-1/2=1/10
b. 39/7:x=13
c. (14/5x-50):2/3=51
d. (x+1/2)(2/3-2x)=0
e. 2/3x-1/2x=5/12
g. (x.44/7+3/7)11/5-3/7=-2
h. x.13/4+(-7/6)x-5/3=5/12
i.93/17:x+(-4/17):x+22/7:52/3=4/11
j. 17/2-|2x-3/4|=-7/4
k. (x+1/5)^2+17/25=26/25
l. -32/27-(3x-7/9)^3=-24/27
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!!
-3x + 24 = -24
17 - 2x = -15
54 : ( x + 2) = -6
12 . ( 3 - x ) = 72
-3. ( x + 5) + 18 + -27
( x + 5 ) 2 = 9
( 3 - x )3 = 27
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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
- 3\(x\) + 24 = -24
3\(x\) = 24 + 24
3\(x\) = 48
\(x\) = 48 : 3
\(x\) = 16
(x-3).(x mũ 2 +3x+9)-(3x-17)=x(x mũ 2 -8) tính X
(x-3)(x2 + 3x + 9) - (3x-17) = x(x2 - 8)
<=> x3 - 27 - 3x + 17 = x3 - 8x
<=> 5x - 10 = 0
<=> 5x = 10
<=> x = 2
Vậy ...