If `a, b, c, d, e and f` are non negative real numbers such that `a +b+c+d+e+f=1`, then the maximum value of `ab + bc + cd + de + ef` is

If a+b+c+d=1 then maximum value of ab+ bc + cd + da

If a, b, c and d are positive real numbers such that a+b+c+d= 1 then prove that ab + bc + cd + da le 1/4 .

Let a,b,c,d and e be positive real numbers such that a+b+c+d+e=15 and ab^2c^3d^4e^5=(120)^3xx50 . Then the value of a^2+b^2+c^2+d^2+e^2 is ___________.

Let a,b,c,d,e, be real numbers such that a+b lt c+d , b+c lt d+e, c+d lt e+a, d+e lt a+b . Then

If a,b,c,d,e are positive real numbers such that,a+b+c+d+e=15 and ab^(2)c^(3)d^(4)e^(5)=(120)^(3).50 then the value of a^(2)+b^(2)+c^(2)+d^(2)+e^(2) is

If a,b,c and d are different positive real numbers in H.P,then (A)ab>cd(B)ac>bd (D) none of these (C)ad>bc