How do you solve and write the following in interval notation: #| x | ≥ 4#?

1 Answer
Sep 6, 2016

#4<=|x|<=oo#

This combines :
#-oo<=x<=-4" and "4<=x<=oo#

Explanation:

Suppose #|x|=4#

Then we have #x= -4" and "x=4#

For #|x|>=4# then the values of #x# progress further and further form 0 in both the positive and negative direction.

For the negative side only this means that #" "-oo<=x<=-4#

For the positive side only this means that #" "4<=x<=oo#

If you desired to combine these into 1 interval you would write:

#4<=|x|<=oo#