\( 3{x^3} - 2{x^2} + 5x + 2\\ = 3{x^3} + {x^2} - 3{x^2} - x + 6x + 2\\ = {x^2}\left( {3x + 1} \right) - x\left( {3x + 1} \right) + 2\left( {3x + 1} \right)\\ = \left( {3x + 1} \right)\left( {{x^2} - x + 2} \right) \)
\( 3{x^3} - 2{x^2} + 5x + 2\\ = 3{x^3} + {x^2} - 3{x^2} - x + 6x + 2\\ = {x^2}\left( {3x + 1} \right) - x\left( {3x + 1} \right) + 2\left( {3x + 1} \right)\\ = \left( {3x + 1} \right)\left( {{x^2} - x + 2} \right) \)
Rút gọn các phân thức: \(\dfrac{3x^3-7x^2+5x-1}{2x^3-x^2-4x+3}\)
A = \(\dfrac{2x^2-5x+2}{x^2-5x+6}\)
B = \(\dfrac{2x^5+3x^4-2x-3}{2x^3+3x^2+ 2x+3}\)
Giải PT sau:
a, 3x - 7 = 0
b, 8 - 5x = 0
c, 3x - 2 = 5x + 8
d, \(\dfrac{3x-2}{3}\) = \(\dfrac{1-x}{2}\)
e, ( 5x + 1)(x - 3) = 0
f, (x + 1)(2x - 3) = 0
g, 4x(x + 3) - 5(x + 3) = 0
h, 8(x - 6) - 2x(6 - x) = 0
i, \(\dfrac{2}{x-1}\) + \(\dfrac{1}{x}\) = \(\dfrac{2x+5}{x^2-x}\)
k, \(\dfrac{3}{x+2}\) - \(\dfrac{2}{x-2}\) = \(\dfrac{2-x}{x^2-4}\)
m, \(\dfrac{3}{x}\) - \(\dfrac{2}{x-3}\) = \(\dfrac{4-x}{x^2-3}\)
n,\(\dfrac{3}{2x+10}\)+ \(\dfrac{2x}{x^2-25}\) = \(\dfrac{3}{x-5}\)
u, \(\dfrac{2}{x+3}\) - \(\dfrac{3}{x-2}\) = \(\dfrac{x+4}{\left(x+3\right)\left(x-2\right)}\)
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
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
1.Giải các phương trình sau:
A) 3x - 2 = 2x - 3
B) 2x + 3 = 5x + 9
C) 5 - 2x = 7
D) 10x + 3 - 5x = 4x + 12
E) 11x + 42 - 2x = 100 - 9x - 22
F) 2x - (3 - 5x ) = 4(x+3)
G) x(x+2) = x(x+3)
h) 2(x-3) + 5x(x-1)=5x2
bài 2: làm tính chia
a. (x^3-3x^2+x_3):(x-3)
b. (x^2+2x+x^2-4):(x+2)
c.(2x^3-5x^2+6x-15):(2x-5)
d. (x^3+2x^2-2x-1):(x^2+3x+1)
Giải các phương trình sau
a) |x-2| = 3
b) |x+1| = |2x+3|
c) |3x| = x+6
d) |x-5| = 13-2x
e) |5x-1| = x-12
f) |-2x| = 3x+4
g) |2x-1| = 6-x
h) |-1+5x| = 8-x
i) |-2x+1| = x+3
k) |-2-5x| = -4x+7
Bài 1: Giải các phương trình sau:
a) 3x – 2 = 2x – 3 b) 5x + 2x – 6x +25 = 0
c) 7 – 2x = 22 – 3x d) 8x – 3 = 5x + 12
Bài 1 : tìm x biết
A. 3x2.(2x3-x+5)
B. (4xy+3y-5x).x2+7
C. (3x-2)(4x+5)-6x(2x-1)
D. (3x-5)(x2-5x+7)