new calculus problem.. HELP!!

[aMo0oDi]

Hi there... i need a help with this question as soon as possible...

Find a positive number such that the sum of the number and its reciprocal is as small as possible..?

[Muzza]

Minimize f(x) = x + 1/x.

[aMo0oDi]

i'm kind of lost here, i need a full answer

[Muzza]

Well, I'm not going to give it to you... How lost are you exactly? Do you know how to calculate the derivative of x + 1/x?

[aMo0oDi]

actually, i don't know how you get x + 1/x.. i can calculate its derivative though.. please explain the way the you got x + 1/x..

thanks..

[Muzza]

x = a number.
1/x = that number's reciprocal.

x + 1/x = a number plus its reciprocal.

[aMo0oDi]

thanks a lot.. i appreciate your help :)