cho a+b+c=0 cmr a^4+b^4+c^4=2(ab+bc+ac)^2
Cho a+b+c=0
CMR : a^4 + b^4 + c^4 = 2 ( ab + ac + bc )^2
Cho a+b+c=0
CMR: (a+b+c)4=2(ab+bc+ac)2
Cho a,b,c dương . a + b + c = 0 CMR : a4 + b4 + c4 = 2(ab + bc + ac)2
Cho (a-b)^2+(b-c)^2+(c-a)^2+4(ab+bc+ac)>=4(a^2+b^2+c^2)
CMR: a=b=c
cho a+b+c=0 . CMR a, ( ab+bc+ca)^2 = a^2b^2+b^2c^2+c^2a^2 b, a^4+b^4+c^4=2(ab+bc+ca)^2
cho a+b+c=0.cm: a^4+b^4+c^4=2(ab+bc+ac)
Cho a+b+c=0 CMR
1. a^4 + b^4 + c^4 = 2( a^2b^2 + b^2c^2 + c^2a^2 )
2. a^4 + b^4 + c^4 = 2( ab + bc + ca )^2
3. a^4 + b^4 + c^4 = (a^2 + b^2 + c^2)^2 /2
Cho a+b+c=0 CMR
a) (ab+bc+ca)2=a2b2+b2c2+c2a2
b) a4+b4+c4=2(ab+bc+ca)2
