non permissable values
posted by Tara on .
i have a hard time understanding the non permissable values could someone please explain. I have solved the following equations but need help determining the values. Also if you could check to see if i did them right it would be alot of help
1. a2+7a+12/a2+4a+4 x a2a6/a29
(Ans)a+4/a+2
2.4/y2+5y+6  5/y2y12
(ans) (y26)/(y+2)(y+3)(y4)
any number following a letter is to the power of

Nonpermissiable values.
You only have to worry about the denominators. A denominator can never be equal to zero since division by zero is not defined.
If a denominator is x + 2 , we don't want it to equal zero. So, x cannot = 2 sind that will cause the denominator to equal zero. 
that makes much more sense thank you i couldn't figure it out
so a restriction is someting that it cannot be divded or multiplied from right? 
ok that helped thank you