x : (-1) = x - 1
=> x = (x - 1).(-1)
=> x = -x + 1
=> x + x = 1 = 2x
=> x = 1/2
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Các câu hỏi tương tự
Tìm x
a) x-6/7 + x-7/8 + x-8/9 = x-9/10 + x-10/11+x-11/12
b) x+32/11 + x+23/12 = x+38/13 + x+27/14
c) | x-2| = 13
d) 3|x-2| + |4x-8| = |-2| - |1/3|
e) |3x-2|+5^-1 = 3 + | x- (2/3) |
f) | x+2 | + | x-2 | = 3
g) (2x-1)^2 - 5 = 20
i) (x+2)^2 = 1/2 - 1/3
k) (x-1)^3 = (x-1)
m) (x-1)^x+2 = (x-1)^2
n) (x+3)^y+1 = (2x-1)^y+1 vs y là 1 số tự nhiên .
tinh gia tri bieu thuc (x-1)^3-4x(x+1)(x-1)+3(x-1)(x^2+x+1) voi x=-2
(x+1/2)+(x+1/4)+(x+1/8)+(x+1/16)=1
tìm x biết
1)(2x+3)^2-(2x+1)(2x-1)=5
2)(x+3)(x^2-3x+9)-x(x^2+5)=20
3)(x+2)^3-x(x^2+6x)=15
4)(x-1)(x^2+x+1)-x(x+10(x-1)=7
5)x^2-9+5(x+3)=0
giúp mk nha!!!
1)(x+7)(3x-1)=49-x^2
2)(2x+1)^2-(x-1)^2=0
3)(1-2x)^2-(x+3)^2+3(x+1)(1-x)=8
4)(x-3)^2-(x+3)^2=24
Giúp mk nha
Chứng minh các đẳng thức sau:
a) (x-1)(x+1)=x2-1; (x-y)(x+y)=x2-y2; (x-y)2=x2-2xy+y2
b) (x+y)2=x2+2xy+y2; x3-1=(x-1)(x2+x+1); x3-y3=(x-y)(x2+xy+y2)
c) x3+1=(x+1)(x2-x+1); x3+y3=(x+y)(x2-xy+y2)
a,(2x+1)2 = (x-1)2
b,(x2-5)(x+3)=0
c, 3(x-1)(2x-1)=5(x+8)(x-1)
d, x3 + x2 +x+1=0
\(\dfrac{x+1}{10}+\dfrac{x+1}{11}+\dfrac{x+1}{12}+\dfrac{x+1}{13}+\dfrac{x+1}{14}\). Tìm x
Tìm x : \(\frac{\left(x-3\right)^2}{2}-1\frac{1}{3}\left(x+2\right)^2-\frac{5}{4}\left(x-1\right)\left(x+1\right)=1\frac{1}{2}x\left(x-2\right)-x-4\)
Rút gọn:
\(\left[\dfrac{3}{x+1}+\left(\dfrac{3}{x+1}-\dfrac{x}{1+2x+x^2}\right):\dfrac{2x^3+3x^2}{x+1}\right]:\dfrac{3x+1}{x^3+x^2}:\left(x-1\right)\)