Inequalities

[imnerd]

i have a question here about inequalities. It sounds like this....

|(x^2)+1|<|(x^2)-9|

since this inequalities have modulus, i square both equations and i get quartic equations, is it any problem here? or i suppose to solve this question in other method?

Plz help, THX!

 

[pka]

One you have squared both; simply solve the resulting inequality,
You should get −2<x<2.

 

[tkhunny]

You may wish to note that x^2 + 1 is NEVER negative. Does the additional notation (absolute value or modulus) do anything in this case?

 

[imnerd]

thx for ur help!