If X^2 >= 100 then it follows that X >= 10 or X<= 0. Is this statement true?
I'm aware that it would certainly be true if the second part was X>= 10 or X<= -10. But I suppose as X<= 0 is more general that X<= -10 (X<=-10 is a subset of X<=0) then it holds as being correct.
I am right in thinking this?
Sorry if this is in the incorrect sub forum...
Thanks for your response, I can quite see that your counter example works well. But it's still giving me some trouble.
If the statement was reduced further to:
X^2 >= 100 then it follows that X>= 0 or X<= 0.
Can't the above statement be summarized by saying 'if X squared is greater or equal to 100 then the X is either a positive number of a negative number or it is zero. This is true is it not?