V
vitconcatinh_foreverloveyou


cho a, b, c,d khac nhau va khac 0 thoa man:
a/b+c=b/a+c=c/a+b
tinh gia tri bieu thuc A= (b+c)/a+(a+c)/b+(a+b)/c
a/b+c=b/a+c=c/a+b
tinh gia tri bieu thuc A= (b+c)/a+(a+c)/b+(a+b)/c