How do you find the domain and range of #f(x)=x^2-1#?

1 Answer
Aug 6, 2018

#x inRR#
#y in[-1,oo)#

Explanation:

#"This is a polynomial of degree 2 and is well defined for"#
#"all real values of x"#

#"domain is "x inRR#

#(-oo,oo)larrcolor(blue)"in interval notation"#

#"to find the range we require the vertex and whether it"#
#"is a maximum or minimum"#

#"the vertex of a parabola in the form "y=ax^2+c#

#"is "(0,c)#

#color(magenta)" vertex "=(0,-1)#

#"since "a>0" then minimum turning point " uuu#

#"range is "y in[-1,oo)#
graph{x^2-1 [-10, 10, -5, 5]}