x,y,z,a,b,c,r>0证明：x+y+a+b/x+y+a+b+c+r+y+z+b+c/y+z+a+b+c+r>x+z+a+c/x+z+a+b+c+r

Question

x,y,z,a,b,c,r>0 证明：x+y+a+b/x+y+a+b+c+r + y+z+b+c/y+z+a+b+c+r>x+z+a+c/x+z+a+b+c+r

Answer 1

设x,y,z,a,b,c,r相等,带进去算,不等式成立