Is this step of this inequation is correct,I got it from a book and I guess its wrong or may be I am missing something
How come the sign changed? To me it doesnt make any sence.
The essence of mathematics lies in its freedom - Georg Cantor
Looks like a typo.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
A number by itself is useful, but it is far more useful to know how accurate or certain that number is.
It's wrong. The sign should've stayed the same...
Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.