Suppose that a b c d are real numbers satisfying `a>=b>=c>=d>=0` `a^(2)+d^(2)=1 and b^(2)+c^(2)=1` and `ac+bd=1/3` .The value of ab-cd is

(a-5)^(2)+(b-c)^(2)+(c-d)^(2)+(b+c+d-9)^(2)=0, then the value of (a+b+c)(b+c+d) is :

If a: b= 5:7 and c:d=2a:3b, then ac: bd is :

If a,b,c,d are such unequal real numbers that (a^(2)+b^(2)+c^(2))p^(2)-2 (ab+bc+cd) p+ (b^(2)+c^(2)+d^(2)) le 0 then a,b,c, d are in -

if a,b, c, d and p are distinct real number such that (a^(2) + b^(2) + c^(2))p^(2) - 2p (ab + bc + cd) + (b^(2) + c^(2) + d^(2)) lt 0 then a, b, c, d are in