## anonymous one year ago ???

1. amistre64

seems like you want to take a derivative to me

2. anonymous

I think thats what they're asking, so I would derive that equation to get 8x

3. amistre64

almost, y' = 8xx'

4. amistre64

do you know what an implicit is?

5. amistre64

or rather, just take the derivative of both sides with respect to time, not with respect to x

6. anonymous

Implicit differentiation?

7. amistre64

yes $y = 4x^2+1$ $\frac{d}{dt}y = \frac{d}{dt}4x^2+\frac{d}{dt}1$ $\frac{dy}{dt} = \frac{dx}{dt}8x+0$

8. amistre64

dx/dt has been defined for us as 2

9. anonymous

So now I would plug in my values?

10. amistre64

of course

11. anonymous

So it is increasing at a rate of 16?

12. amistre64

correct

13. amistre64

the key is seeing that x' is not defined as dx/dx in this case, so we take a derivative implicitly with respect to time, and not to x

14. anonymous

Okay ill remember that for next time, thank you so much for your help!!!!!!

15. amistre64

good luck