Biết \(x^2-2x-1=0\). Tính biểu thức \(\dfrac{x^6-6x^5+12x^4-8x^3+2015}{x^6-8x^3-12x^2+6x+2015}\)
tim x (X/2+3)(5-6X)+(12X-2)(X/4+3)=0
Tìm x:
a)(x-1)^2+x(5-x)=8
b)x^3-3x^2+x-3
c)(12x^4-6x):6x+2x(2+x)(2-x)=7
1) (y-z)(12x^2-6x)+(y-z)(12x^2+6x)
2) a(b-c)+d(b-c)-c(c-b)
3) a(b-3)+(3-b)-b(3-b)
4) 5(a-b)^2+(a+b)(a-b)
5) 2a(x-y)-(y-x)
6) a^2(x-y)-(x-y)
7) 6x^2 -3+7x(6x^2-3)+4y(3-6x^2)
(x/2+3)(5-6x)+12x-2+(x/4+3)=0
Tìm x
Bài 4: Tìm x, biết.
a) 4x(x - 7) - 4x2 = 56
b) 12x(3x - 2) - (4 - 6x) = 0
c) 4(x - 5) - (5 - x)2 = 0
d) x(x +1) - x(x - 3) = 0
e) - 6x + 8 = 0 f) 2 + 2x + = 0
Tìm x biết rằng:
a) ( x 2 + 2x + 4)(2 - x) + x(x - 3)(x + 4) - x 2 + 24 = 0;
b) x 2 + 3 ( 5 − 6 x ) + ( 12 x − 2 ) x 4 + 3 = 0 .
Bài 3 : Tìm x biết
a) (x-2)^2-x(x-3)=0
b) (x+3)(2x+1)-2(x-1)^2=0
c) (4x-5)^2=9(2-5x)^2
d) X^2-6x-13=0
e) (x+2)(x^2-2x+4)-x(x^2+2)=15
f) X^3-6x^2+12x-19=0
Tìm x biết
x^3 + 6x^2 +12x= 19
5(x + 9)^2(x - 4)^3 - 10(x + 9)^3(x - 4)^2 = 0
(2x + 3)^2 + (x - 2)^2 - 2(2x +3 )(x - 2)