[" For any two real numbers "A,B" cos "],[(A+B)cos(A-B)=]

For any two real numbers C and D , cosC+cos D=

For any angles A and B, cos(A+B).cos(A-B)=…..

For any two real numbers a and b, sqrt((a-b)^2)+sqrt((b-a)^2) is

For any real number of x and y, if cos x=cos y then:

For any two real numbers a and b,we define a R b if and only if sin^(2)a+cos^(2)b=1. The relation R is

For any two real numbers a and b , we define aRb if and only if sin ^(2) a +cos ^(2) b=1 , the relation R is -

In any triangle, (1+ cos (A-B)cos C)/(1+cos (A-C)cos B)=

For any two real number a and b ,we define a R b if and only if sin^2a + cos^2b = 1 . The relation R is

For any two real numbers, an operation ** defined by a**b=1+ab is

For any two real numbers, an operation '*' defined by a*b = 1 + ab is