1) - Phan tich cac da thuc sau thanh nhan tu :
a) 14x2y2 - 21xy2 + 28x2y d) 2 phan 7 x(3y -1 )-2 phan 7y (3y-1)
b) x3 -3x2 + 3x- 1 e) (x+y)2-4x2
c) 27x2+1phan 8 f) (x+y)3-(x-y)3
2) tim x biet
a) x2(x+1)+2x(x+1)=0 b) x(3x-2)-5(2-3x)=0
c) 4 phan 9 -25x2=0 d) x2-x+phan4=0
3) tinh nhanh cac gia tri bieu thuc sau :
a) 17.91,5+170.0,85 b) 20162-162
c) x(x-10-y(1-x)tai x=2001va y = 2999
Chung to gia tri cua bieu thuc ko phu thuoc vao gia tri cua bien: M=(3+x)-(4x+1)-x(2+x)
Ai giai dum☺cach lam luon nha
A= (1/3+ 3/(x^2 -3*x)) /(x^2/(27 -3*x^2) + 1/(x + 3))
a, rut gon A
b, tim x de A< -1
c, voi gia tri nao cua x thi A nguyen
tinh a4+b4+c4 tai a+b+c=38; ab+bc+ca=20
rut gon bieu thuc
3(2^2+1).(2^4+1)...(2^64+1)+1
cho a+b+c=1;a^2+b^2+c^2=1,a^3+b^3+c^3=1. Tính giá trị của a,b,c
phan tich da thuc thanh nhan tu : \(a^6+a^4+a^2b^2+b^4-b^6\)
1.(a+b+c)^3-(a+b+c)^3-(a-b+c)^3-(-a+b+c)^3
2)x^3+ax^2-7x-10
3)(x^2+x)^2-(x^2+x)+15
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)