How do you find values of x where the function f(x)=sqrt(x^2 - 2x) is continuous?

1 Answer
Feb 20, 2015

The answer is: (-oo,0] uuu [2,+oo).

The domain of a square root (and of all the roots with even index) like sqrtf(x), is f(x)>=0,

so:

x^2-2x>=0rArrx(x-2)>=0,

considering that 0 and 2 are the solutions of the equation:

x(x-2)=0 and considering that the inequality is >=, than the solutions are for external values,

so:

x<=0vvx>=2, or, in another notation,

(-oo,0]uuu[2,+oo).