Hi all!
I've been working with differentiation for quite some time now, and I know how to use the product rule.
f(x) = u(x)*t(x)
f'(x) = u'(x)*t(x) + t'(x)u(x)
But what I don't understand is how one derives it... :cry:
Oh, and one more thing.
How do we know a number is irrational...