An element `x` is added to the set `{1,2,3,4}` so that its variance remains the same. The sum of all values of `x` is

If "cos"^(-1)x> "sin"^(-1)x , then the set of all values of x is

The minimum number of elements that must be added to the relation R={(1,2),(2,3)} on the set of natural numbers so that it is an equivalence is

If the variance of 1,2,3,4,5,….., x is 10, then the value of x is

The minimum number of elements that must be added to the relation R = { (1,2), (2,3)} on the set of natural numbers so that it is an equivalence is

If the variance of 1, 2, 3, 4, 5, ... , x is 10, then the value of x is

Let A=[(1//2, 3//4),(1, -1//2)] , then the value of sum of all the elements of A^(100) is

In an infinite G.P. second term is x and its sum is 4, then complete set of values of x is in