Cho biểu thức:: A=2/3x - x/x+2 + 9x^2-4/3x(x+2) với x khác 0 và -2
a) CMR: A= 6x+2/3x+6
b)tìm x đến A>2
tìm x
a) (x+2)(x+3)-(x-2)(x+5)=6
b) (3x+2)(2x+9)-(x+2)(6x+1)=(x+1)-(x-6)
c) 3(2x-1)(3x-1)-(2x-3)(9x-1)=0
Bài 5: Tìm a , b để các đa thức sau:
1) x^4+6x^3+7x^2-6x+a chia hết cho x2+3x-1
2) x^4-x^3+6x^2-x+a chia hết cho x^2- x+5
3) x^3+3x^2+5x+a chia hết cho x+3
4) x^3+2x^2-7x+a chia hết cho 3x -1
5) 2x^2+ax+1 chia cho x-3 dư 4
tim x biet
a/(3x-5)(2x-1)-(x+2)(6x-1)=0
b/ (3x-5)(3x+2)-(3x-1)2=-5
c/(3x+2)(x-5)=3(x-1)2-2
d/ (x+1)2/3 - (x-2)2/2 = 2x+1/2 (x-3)2/6
g/49x2=(3x+2)2
h/(3x-4)2-(2x-2)2-3(x-2)(2x-1)=0
i/ (x-2)(x2-2x+4)-x(x2+2)=15
k/ 6x2-7x-3=0
m/(x+5)(x-3)+x2-25=0
e/ x3+3x2=4x+12
f/ (6x+7)2(3x+4)(x+1)=6
phân tích đa thức thành nhân tử
1)2x^2+3x-5
2)16-5x^-3
3)x^2+x-6
4)x^2+8x-9
5)x^2+x-12
6)x^8+1024
7)x^7+x^2+1
8)x^8+3x^4+4
9)(x^2+x+1)(x^2+x+2)-12
10)x(x+1)(x+2)(x+3)+1
11)x^4+6x^3+11x^2+6x+1
12)3x^2+11x^3-7x^2-2x+1
làm phép chia :
a) (x^4 -2x^3 + 2x -1) : (x^2 - 1)
b) (x^3 -8) : (x^2 + 2x +4)
c) (x^6 - 2x^5 + 2x^4 + 6x^3 - 4x^2)n: 6x^2
d) (-2x^5 + 3x^2 - 4x^3) :2x^2
e) (15x^3 - 10x^2 + x - 2) : (x - 2)
f) (2x^4 - 3x^3 - 3x^2 + 6x - 2) : (x^2 - 2)
3x^4 + 3x^2y^2 + 6x^3y - 27x^2
x^4 + x^3 - x^2 + x
2x^5 - 6x^4 - 2a^2x^3 - 6ax^3
x^5 + x^4 + x^3 + x^2 + x + 1
x^3 - 1 + 5x^2 - 5 + 3x - 3
1/4.(a + 1)^2 - 4/9.(a - 2)^2
12a^2b^2 - 3.(a^2b^2)^2
4x^2y^2 - (x^2 + y^2 - a^2)^2
(a + b + c)^2 + (a + b - c)^2 - 4c^2
x^3 - 1 + 5x^2 - 5 + 3x - 3
a)2x-3/4-4x-5/3=5-x/6
b)3(x-1^2)=16
c)(x+7)(x-4)=2(x-4)
d)4x^2-3x-1=0