## jpjones Group Title derivative of (t-1/t) one year ago one year ago

1. vf321 Group Title

For t!=0, f(t) = 1-(1/t). Do you know how to derive that?

2. alexray19 Group Title

Do you mean $\frac{t-1}{t}$ or $t-\frac{1}{t}$?

3. jpjones Group Title

the second one

4. vf321 Group Title

Oh nvm forget my answer then.

5. alexray19 Group Title

Well you're just doing two separate derivatives then. One for t, and one for -1/t. Can you do these separately?

6. jpjones Group Title

no i wouldn't have asked othewrwise

7. jpjones Group Title

i think the derivative of t is zero

8. alexray19 Group Title

You don't know what the derivative of t is?

9. jpjones Group Title

or 1

10. alexray19 Group Title

No, 0 is only the derivative of a constant. For example, the derivative of the number 5 is 0. t is a variable that changes, so its derivative can't be 0 (that would imply it's not changing). Yes, 1 is correct for t.

11. jpjones Group Title

now -1/t?

12. wio Group Title

Use to power rule: $\frac{d}{dx}x^n = n\cdot x^{n-1}$ In the first case, n = 1, and in the second case n = -1.

13. alexray19 Group Title

If you know the power rule, you can use it to derive -1/t by first rewriting it as $-t^{-1}$

14. jpjones Group Title

thank wio