giup minh gai bai nay voi nha
a, <x+y+z+>mu 2
b , <x+y-z-d>mu 2
bai 1 cmm hang dang thuc
a,(a+b+c)^2 +a^2+b^2+c^2=(a+b)^2+(b+c)^2+(c+a)^2
b, x^4+x^4+(x+y)^4=2(x^2+xy+y^2)^2
giAI HO MINH NHE NHANH LEN MINH DANG GAP
ai giup minh giai bai nay voi
1<=z, y, z<=2
tim gia tri lon nhat
A=(x+y+z)(1/x+1/y+1/z)
Chung minh dang thuc
a)(x+a)(x+b)=x2+(a+b)x+ab
b)(x+a)(x+b)(x+c)=x3+(a+b+c)x2+(ab+bc+ca)x+abc
c)(x-y-z)2=x2+y2+z2-2xy+2yz-2zx
d)(x+y-z)2=x2+y2+z2+2xy-2yz-2zx
e)(x+y+z)3=x3+y3+z3+3(x+y)(y+z)(z+x)
lam on giup minh nha minh can rat gap thanks
Viet moi bieu thuc sau duoi dang 2binh phuong :
a; ( x+ y+4 ) .(x+y-4)
b; (x-y+6).( x+y-6)
c: ( x+2y+3z). (2y+3z-x)
Giup minh vs <3
lop8 Hang dang thuc nhaa .
phan tich thanh hang dang thuc x^2+y^2+z^2
1. viet cac bieu thuc sau duoi dang tong
a) (2x+3y)2 ; (0,01+xy)2
b) (x-2y).(x-2y) ; (56.64)
c) (x-y+z).(x+y+z)
d) (x+y+z).(x-y-z)
e) (x+1).(x-1)
phan tich da thuc thanh nhan tu
x^2-x-y^2-y
x^2-2xy+y^2-z^2
bai 32 va 33 sbt
lop 8 bai phan tich da thuc thanh nhan tu bang cach nhom hang tu
1) Phan tich da thuc sau thanh nhan tu: x2-x-2008.2009
2) Chung minh rang voi moi x,y,z ta luon co: x2+4y2+z2>=2x+12y+4z
3) Cho a-b=4. Tinh gia tri cua bieu thuc: a3-12ab-b3
cac ban lam duoc cau nao thi giup mik nha. mik dang can gap lam