Evaluate :

`x^2 - ( 1 - x )^2` is equal to:

Evaluate : x + 1/x= 4 , x^2 + 1/x^2

If x + (1)/(x) = 8 , then x^(2) + (1)/(x^(2)) is equal to :

The minimum value of [x_(1)-x_(2))^(2)+(12-sqrt(1-(x_(1))^(2))-sqrt(4x_(2))]^((1)/(2)) for all permissible values of x_(1) and x_(2) is equal to a sqrt(b)-c where a,b,c in N, the find the value of a +b-c

lim_(x to 0) (sqrt(1 + x + x^(2)) - sqrt(x + 1))/(2X^(2)) is equal to