Lời giải:
$(x-2)-x^2+4=0$
$\Leftrightarrow (x-2)-(x^2-4)=0$
$\Leftrightarrow (x-2)-(x-2)(x+2)=0$
$\Leftrightarrow (x-2)[1-(x+2)]=0$
$\Leftrightarrow (x-2)(-1-x)=0$
$\Rightarrow x-2=0$ hoặc $-1-x=0$
$\Leftrightarrow x=2$ hoặc $x=-1$
Lời giải:
$(x-2)-x^2+4=0$
$\Leftrightarrow (x-2)-(x^2-4)=0$
$\Leftrightarrow (x-2)-(x-2)(x+2)=0$
$\Leftrightarrow (x-2)[1-(x+2)]=0$
$\Leftrightarrow (x-2)(-1-x)=0$
$\Rightarrow x-2=0$ hoặc $-1-x=0$
$\Leftrightarrow x=2$ hoặc $x=-1$
tìm x , biết :
a, ( x mũ 3 - 4 x mũ 2 ) - ( x -4 ) = 0
b, x mũ 5 - 9x = 0
c, ( x mxu 3 - x mũ 2 ) mũ 2 - 4 x mũ 2 + 8x - 4 = 0
5A. Tìm x, biết:
a) 8x(x - 2017) - 2x + 4034 = 0; b)
x + x2
![]()
2 8
= 0;
c) 4 - x = 2( x -4)2; d) (x2 + 1)(x - 2) + 2x = 4.
5B. Tìm x, biết:
a) x4 -16x2 =0; c) x8 + 36x4 =0;
b) (x - 5)3 - x + 5 = 0; d) 5(x - 2 ) - x2 + 4 = 0.
Bài 4: Tìm x:
1) x2 - 9x = 0 2) x(x - 4) – x2 = 7 3) 3x + 2(x – 5) = 5
4) 25x2 - 1 = 0 5) 3x(x - 2) - 5(x - 2) = 0 6) 3x(x - 7) + 4(x – 7) = 0
7) 4x2 – 9 = 0 8) 10x(x - 4) + 2x - 8 = 0 9) x(2x - 5) - 2x2 = 0
10) 2x2 – 4x = 0 11) 2x(3 - 4x) + 3(4x - 3) = 0 12) 2x (x – 5) – 2x2 = 3
mọi người giúp mình vs chiều 1g mình thi rồi! cảm ơn!![]()
Tìm x, biết:
a) x(x-2)+x-2=0
b) 2/3x( x^2-4) =0
g)(x+2)^2 -x+4=0
h)(x+2)^2= (2x-1)^2
BT2: Tìm x 2, 3x(x-4)+2x-8=0 3, 4x(x-3)+x^2-9=0 4, x(x-1)-x^2+3x=0 5, x(2x-1)-2x^2+5x=16
tìm x: a)x^4-2x^3+5x^2-10x=0
b)(3x+5)^2=(2x-2)^2
. c)x^3–2x^2+x=0
. d)x^2(x-1)-4x^2+8x-4=0
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:
a/ 5x( x- 3) = x – 3 b/ x3 - x = 0 c/ x2 – 7x + 6 = 0
d/ x2 – 4 + ( x – 2)2 = 0 e/ x2 – 16 –( x +4) = 0 f/ x2 + x – 2 = 0
Tìm x :
a) \(\left(x^2-2x\right)^2+3\left(x^2-2x\right)+2=0\)
b) \(\left(x^2+x\right)\left(x^2+x-4\right)+4=0\)
tìm x biết x^2 (x^2+ 4 ) - x^2 -4 = 0