Question

the range of f(x)=x²-2=​

Answer 1

Answer:

Step-by-step explanation:

For all x belonging to R, x^2 is always greater than or equal to 0. x^2 is greater than or equal to 0, so x^2+2 must be greater than or equal to 2. So range of the function is [2, infinity).

You can also have another approach. This can be applied to most of the problems. Let y=x^2+2, x=(y-2)^(1/2). For x to belong to R, y-2 must be greater than or equal to 0 else if y-2 will be less than 0, x will not belong to R. So y must belong to [2, infinity).

Both the methods are similar. The 2nd method can be applied to most of the problems.