## steel11 3 years ago implicit differentiation help. Somebody here has got to know how to do this problem... >.< http://gyazo.com/53dfb49c3ca8d1a3b949b4f9f2afa67c

1. vf321

Do you know the power rule?

2. steel11

yes

3. steel11

i know how to get y' alone. im having problems putting it in the formular y-y1=m(x-x1)

4. vf321

How so?

5. Coolsector

(2/3) * x^-(1/3) + (2/3) * y^-(1/3) * (dy/dx) = 0 dy/dx = -x^(-1/3) / y^(-1/3)

6. steel11

yes, got that far. now what coolsector?

7. vf321

Fill in y

8. vf321

and x

9. Coolsector

plug x = -3sqrt(3) , y= 1

10. steel11

i filled in both x and y. and got a number. i used that as my slope in the equation y-y1=m(x-x1)

11. Coolsector

you get dy/dx = - (3sqrt(3))^(-1/3)

12. steel11

yes, which is -1.732 corect?

13. Coolsector

mm i ges -0.577 in fact

14. Coolsector

and x1 = -3sqrt(3) y1 = 1...

15. steel11

dy/dx = -x^(-1/3) / y^(-1/3) i replaced x and y with given points in this, and got -1.732

16. Coolsector

dy/dx = -(3sqrt(3))^(-1/3) / 1

17. Coolsector

dy/dx = -(3sqrt(3))^(-1/3) i get -0.577

18. steel11

ok. go on with that then. what is the final answer?

19. steel11

need an equation in y= form

20. Coolsector

y =1 -0.577(x+3sqrt(3)) y= 1 -0.577x -3 y = -0.577x -2

21. Coolsector

in fact dy/dx = -1/sqrt(3) so : y = -x/sqrt(3) -2

22. Coolsector

$y = \frac{ -x }{ \sqrt{3} } -2$

23. steel11
24. steel11

says incorrect :/

25. Coolsector

if we plug x = -3sqrt(3) we get y = 1 right ?

26. steel11

yes

27. Coolsector

well weird

28. steel11

yeah, i have no idea how to do this problem :/ thanks anyways

29. Coolsector

im sure it is correct

30. steel11

just tried putting in again, says wrong. :|

31. steel11

going to close post and make another one.