(a+b-c)^2 + (a-b+c)^2 - 2(b-c)^2
= (a + b - c)^2 - (b - c)^2 + (a - b + c)^2 - (b - c)^2
= (a + b - c + b - c)(a + b - c - b + c) + (a - b + c - b + c)(a - b + c + b - c)
= a^2 + a^2
= 2.a^2
Rut gon bieu thuc: (a-b+c)^2+2(a-b+c)(b-c)+(b-c)^2
Rut gon bieu thuc : (a+b-c)2 + (a-b+c)2 -2(b-c)2
rut gon bieu thuc
(a+b-c)2+(a-b-c)2+(b-c-a)2+(c-b-a)2
rut gon bieu thuc
(a+b)\(^2\)+(b+c)\(^2\)+(c+a)\(^2\)-3(a+b)(b+c)(c+a)
cho a,b,c khac nhau doi mot va 1/a+1/b+1/c=0.rut gon cac bieu thuc
N=bc/a^2+2bc+CA/B^2+2AC+AB/C^2+2AB
rut gon bieu thuc sau:
(a2+b2+c2)-(a2+b2+c2)2
giai dum minh bai nay voi :c=x/2x-2+x^2+1/2-2x^2
a)tim x de a co nghia
b)rut gon bieu thuc c
c)tim gia tri cua x de bieu thuc kia =1/2
giúp mình cảm ơn nhìu nha !
B1: rut gon bieu thuc
a, (x+y)^2-4(x-y)^2
b, 2(x-y)(x+y)+(x+y)^2+(x-y)^2
B2: tim X
a, (2X-1)^2-4(X+2)^2=9
b, 3(X-1)^2-3X(X-5)=21
B3: Cho bieu thuc
M=(x+3)^3-(x-1)^3+12x(x-1)
a, Rut gon bieu thuc tren
b, Tinh gia tri M tai x=-2/3
c, Tim x de M=16
cho 2 bieu thuc A=x+x^2/2-x va B=2x/x+1+3/x-2-2x^2+1/x^2-x-2 a, tinh gia tri cua A khi /2x-3/=1 b,tim dieu kien xac dinh va rut gon bieu thuc B c,tim so nguyen x de P=A.B dat gia tri lon nhat
mk dang can gap
