What is the domain and range of F(x) = 1/ sqrt(4 - x^2)F(x)=14x2?

1 Answer
Jul 8, 2018

The domain is x in (-2,2)x(2,2). The range is [1/2, +oo)[12,+).

Explanation:

The function is

f(x)=1/sqrt(4-x^2)f(x)=14x2

What'under the sqrt sign must be >=00 and we cannot divide by 00

Therefore,

4-x^2>04x2>0

=>, (2-x)(2+x)>0(2x)(2+x)>0

=>, {(2-x>0),(2+x>0):}

=>, {(x<2),(x> -2):}

Therefore,

The domain is x in (-2,2)

Also,

lim_(x->2^-)f(x)=lim_(x->2^-)1/sqrt(4-x^2)=1/O^+=+oo

lim_(x->-2^+)f(x)=lim_(x->-2^+)1/sqrt(4-x^2)=1/O^+=+oo

When x=0

f(0)=1/sqrt(4-0)=1/2

The range is [1/2, +oo)

graph{1/sqrt(4-x^2) [-9.625, 10.375, -1.96, 8.04]}