(1) If a, b, c are natural no. than find out the probability of a2+b2+c2 is divisible by 7.
(2) Find out the minimum non negative value of a, b, c if the polynomials x4+ax3+bx2+cx+d has real root.
(3) Find out the maximum value of (x-a)(x-b)(x-c)(ax+by+cz).If it is given that all a,b,c,(x-a),(x-b),(x-c) are positive.
(4) If f(x) = (a/x) + (b/x+b)-(c/x+c)-(d/x+d), and f(x) is divisible by x2, than find out the value of (1/a) + (1/b)-(1/c)-(1/d).
(5) Find all +ve integers a, b such that each of the equations x2-ax+b=0 and x2-bx+a=0 has distinct +ve integrals root.