How do you find the domain of #y= x^2-2#?

2 Answers
Jun 1, 2018

Answer:

#x in RR#

Explanation:

#x^2-2# is a polynomial, which is defined for all real numbers.

This isn't something mysterious and earth-moving about polynomials, but any number, we can square it, and take it to whatever power for that matter and get a result. And we can subtract #2# from everything. Thus

#x inRR#

Hope this helps!

Jun 1, 2018

Answer:

Domain: #{x|x " is " RR}# or #(-oo, oo)# in interval notation.

Range: #{y|y >=-2)# or #[-2, oo)#

Explanation:

This function is a quadratic #ax^2+bx+c# and all quadratics are parabolas their domain is not restricted and is all real numbers:

Domain: #{x|x " is " RR}# or #(-oo, oo)# in interval notation.

The range is more interesting as it is shifted down 2 from the parent function:

Range: #{y|y >=-2)# or #[-2, oo)#

graph{x^2 -2 [-10, 10, -5, 5]}