(3x-1)^3=-8/27
(3x-1)^3=-8/27
\(\Leftrightarrow3x-1=-\dfrac{2}{3}\)
hay x=1/9
\(\Rightarrow3x-1=-\dfrac{2}{3}\Rightarrow3x=\dfrac{1}{3}\Rightarrow x=\dfrac{1}{9}\)
3x+1= 27
(2x-1)3=8
1) \(3^{x+1}=27\)
\(\Leftrightarrow3^{x+1}=3^3\)
\(\Leftrightarrow x+1=3\Leftrightarrow x=2\)
2) \(\left(2x-1\right)^3=8\)
\(\Leftrightarrow\left(2x-1\right)^3=2^3\)
\(\Leftrightarrow2x-1=3\Leftrightarrow2x=4\Leftrightarrow x=2\)
3x+1=27
3x+1=33
x+1=3
x=2
(2x-1)3=8
(2x-1)3=23
2x-1=2
2x=3
x=3/2
\(3^{x+1}=27\)
\(\Leftrightarrow x+1=3\)
hay x=2
\(\left(2x-1\right)^3=8\)
\(\Leftrightarrow2x-1=2\)
hay \(x=\dfrac{3}{2}\)
Tìm x, biết: (3x-1)3 = (-8)/27
Hằng đẳng thức :x^2+x+1/4
27+8x^3
-x^3+3x^2-3x+1
8+36x+54x^2+27x^3
\(x^2+x+\dfrac{1}{4}=\left(x+\dfrac{1}{4}\right)^2\)
\(8x^3+27=\left(2x+3\right)\left(4x^2-6x+9\right)\)
\(-x^3+3x^2-3x+1=\left(-x+1\right)^3\)
(3x-1)3=-8/27
ta có : \(\left(3x-1\right)^3=\left(-\frac{2}{3}\right)^3\)
=> \(3x-1=-\frac{2}{3}\)
=> \(3x=\frac{1}{3}\)
=> \(x=\frac{1}{9}\)
Vậy \(x=\frac{1}{9}\)
(3x-1)^3=-8/27
x/-15=-60/x
x2012=2012
(3x-1)3=-8/27
-2/x=-x/8/25
(8x-1)2n=52n
(x-2/3)3=(2/3)6
\(\left(3x-1\right)^3=-\frac{8}{27}\)
\(\left(3x-1\right)^3=\left(-\frac{2}{3}\right)^3\)
\(3x-1=-\frac{2}{3}\)
\(3x=-\frac{2}{3}+1\)
\(3x=-\frac{2}{3}+\frac{3}{3}\)
\(3x=-\frac{1}{3}\)
\(x=-\frac{1}{3}\div3\)
\(x=-\frac{1}{3}\times\frac{1}{3}\)
\(x=-\frac{1}{9}\)
Tìm x:
(3x-1)^3=8/27
\(\left(3x-1\right)^3=\frac{8}{27}\)
\(\Rightarrow\left(3x-1\right)^3=\left(\frac{2}{3}\right)^3\)
\(\Rightarrow3x-1=\frac{2}{3}\)
\(\Rightarrow3x=\frac{5}{3}\)
\(\Rightarrow x=\frac{5}{3}:3\)
\(\Rightarrow x=\frac{5}{9}\)
tíc mình nha
a/ (3x+ 1/2)3 = -27/8
b/ 12-3x2 = -3
\(a/\left(3x+\frac{1}{2}\right)^3=\left(-\frac{3}{2}\right)^3\Leftrightarrow3x+\frac{1}{2}=-\frac{3}{2}\Leftrightarrow x=-\frac{2}{3}\)
\(b/-3x^2+15=0\Leftrightarrow3\left(5-x^2\right)=0\Leftrightarrow5-x^2=0\Leftrightarrow x=\pm\sqrt{5}\)
Tìm X
A, (X+1)(X+2)(X+5) - X^2(X+8)=27
B, 1/4 X^2-(1/2X-4)1/2X=-14
C, 3(1-4X)(X-1)+4(3X-2)(X+3)=-27
D,(X+3)(X^2-3X+9) - X(X-1)(X+1)=27