Method III in the method to test the equality of two rational numbers `a/b and c/d ` we use the following result : ` a/b = c/d <=> a xx d = b xx c `

Method III in the method to test the equality of two rational numbers (a)/(b) and (c)/(d) we use the following result: :(a)/(b)=(c)/(d)hArr a xx d=b xx c

If a xx b = c xx d, a xx c = b xx d then

Let A = Q xx Q, where Q is the set of all rational numbers, and * be abinary operation defined on A by (a, b) * (c, d) = (ac, b + ad), for all (a, b) (c, d) in A.Find the identity element in A.

Let A = Q xx Q , where Q is the set of all rational numbers and * be a binary operaton on A defined by (a,b) * (c,d) = (ac, ad+b) for all (a,b), (c,d) in A. Then find the identify element of * in A.

Two planes are perpendicular to one another. One of them contains vectors a and b and the other contains vectors c and d, then (a xx b).(c xx d) equals

Let the positive numbers a , b , c , d be in AP. Then a b c ,a b d ,a c d ,b c d are

Let ~ be a relation defined on N xx N as follows: (a,b),(c,d) in N xx N, (a,b) ~ (c,d) if ad = bc, then