Các câu hỏi tương tự
CM dang thuc
a, ( x - y )^2 = ( x + y )2 - 4xy
b, ( x + y + z )^2 - ( xy + yz + zx ) = 1/2 ( x + y )^2 + 1/2 ( y + z )^2 + 1/2( z + x )^2
chung minh cac hang dang thuc sau luon co gia tri duong voi moi gia tri cua bien
4)D=x^2 -2x+y^2+4y+6
5)P=(15x - 1)^2+3(7x+3)(x+1) -(x^2 -73)
( x2 + y2 ) ( 1/x3 + 1/y3 ) = 6a2 - 5a +1 / a3 voi x+y=1, xy=a , x,y,a khac 0
De bai la chung minh dang thuc, giup minh nhe !!!!
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
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)
Chung minh bat dang thuc sau: \(\frac{x^2}{y^2}\)+\(\frac{y^2}{x^2}\)+4>=3(\(\frac{x}{y}\)+\(\frac{y}{x}\))
Giup mk voi . mk can gap lam. Neu thich thi ket ban voi mk nhe
cmr khong co cac so x,y,x thoa man moi dang thuc sau: A = 2x^2 + y^2 - 2xy + x + 2 = 0
BAI 1 CM DANG THUC
a,(x+y)2 -y2 =x(x+2y)
b,(x2+y2)2-(2xy)=(x+y)2(x-y)
BAI 2;TIM GTNN
a,4a2+4a+2
b.x2-4xy+5y+10x-22y+28
chung minh bieu thuc sau khong phu thuoc va x va y
a ) M = 3x( x - 5y ) + ( y - 5x )( -3y ) - 3(x^2 - y^2 ) - 1
b ) cho S = 1 + x + x^2 + x^3 + x^4 + x^5 cm : xS - S = x^6 - 1