Giair pt:
c, x ( 3x-1) (3x+1) (3x+2) =8
d, (x+1) (2x+3) (2x+5) (x+3)=45
e,x4+ 3x3 - 15x2 - 19x + 3 = 0
f, \(\frac{1}{x^2+x}+\frac{1}{x^2+3x+2}+\frac{1}{x^2+5x+6}+\frac{1}{x^2+7x+12}=\frac{1}{3}\)
h,\(\frac{1}{x^2+9x+20}+\frac{1}{x^2+11x+30}+\frac{1}{x^2+13x+42}=\frac{1}{18}\)
(x2-3x+2)(x2+15x+56)+8=0
(2x2-3x+1)(2x2-5x+1)-9x2=0
\(\dfrac{1}{x^2-3x}+\dfrac{1}{x^2+3x}+\dfrac{1}{x^2+9x+18}+\dfrac{3}{8}=0 \)
a) (x+1/x-2)^2 + x+1/x-4 -3(2x-4/x-4)^2 = 0
b) 15x/x^2 +3x-4 - 1 = 12(1/x+4 + 1/3x-3)
c) x^2-4x+1/x+1 + 2 = - x^2-5x+1/2x+1
3) \(\frac{1-x}{x+1}-\frac{3+2x}{x+1}=0\)
13) \(\frac{x+2}{x}-\frac{x^2+5x+4}{x\left(x+2\right)}=\frac{x}{x+2}\)
14) \(\frac{1}{x+1}-\frac{5}{x-2}=\frac{20}{\left(x+1\right)\left(2-x\right)}\)
16) \(\frac{x+5}{x-5}-\frac{x-5}{x+5}=\frac{20}{x^2-25}\)
17) \(\frac{3x+2}{3x-2}-\frac{6}{2+3x}=\frac{9x^2}{9x^2-4}\)
18) \(\frac{x-1}{x}+\frac{1}{x+1}=\frac{2x-1}{2x^2+2}\)
19) \(\frac{2}{x+1}-\frac{3x+1}{\left(x+1\right)}=\frac{1}{\left(x+1\right)\left(x-2\right)}\)
20) \(\frac{x+5}{3x-6}-\frac{1}{2}=\frac{2x-3}{2x-4}\)
d) (5x+3) ( 4x-1) +(10x-7) (-2x+3) =27
e)(8x-5) (3x+2) -(12x+7) (2x-1)=17
f) (5x+9) (6x-1) -(2x-3)( 15z+1) = -190
g) 6x(5x+3) + 3x(1-10x) =7
h) (3x-3) (5 -21x) +(7x+4)(9x-5) =44\
i) (x+1)(x+2)(x-5)-x2 (x+8)=27
10 Phân tích các đa thức sau thành nhân tử:
a) 5xy(x-y)-2x+2y ; b) 6x-2y-x(y-3x)
c) x^2+4x-xy-4y ; d) 3xy+2z-6y-xz
11 Tìm x, biết: a) 4-9x^2=0 ; b) x^2+x+1/4=0 ; c) 2x(x-3)+(x-3)=0
d) 3x(x-4)-x+4=0 ; e) x^3-1/9x=0 ; f) (3x-y)^2-(x-y)^2=0
Cho \(P=\dfrac{3x^2+15x-6}{9x^2-1}\) với \(x\ne\pm\dfrac{1}{3}.\)
Giá trị của P khi 10x^2 + 5x - 3 =0
Tìm x, biết:
(4x-1)2-(3x+2)(3x-2)= (7x-1)(x+2)+(2x+1)2-(4x2+7)
(5x-1)(x+1)-2(x-3)2= (x+2)(3x-1)-(x+4)2+(x2-x)
(-x+5)(x-2)+(x-7)(x+7)= (3x+1)2-(3x-2)(3x+2)
(2x+3)2-(5x-4)(5x+4)= (x+5)2-(3x-1)(7x+2)-(x2-1)
(1-3x)2-(x-2)(9x+1)= (3x-4)(3x+4)-9(x+3)2
