## mathcalculus 2 years ago finding critical points with polynomial functions (attached)

1. mathcalculus

2. mathcalculus

is it possible to use quadratic formula for this since it can't be factored...?

3. abb0t

To find critical points you need to take a derivative.

4. mathcalculus

okay, so -6x-7

5. mathcalculus

@abb0t

6. abb0t

Now, set it equal to zero and find the roots. Those value(s) are your critical point(s).

7. mathcalculus

i found one.

8. mathcalculus

@abb0t

9. mathcalculus

x=-7/6

10. abb0t

Yes,

11. mathcalculus

critical point is ((-7,6),0)?

12. mathcalculus

it's marking me wrong.

13. mathcalculus

@abb0t

14. abb0t

why is it 0 when you clearly found the value to be $$\frac{7}{6}$$...

15. mathcalculus

that's the problem.. after i find the critical point what do i do?

16. mathcalculus

@abb0t

17. mathcalculus

how would i write the point?

18. abb0t

That is your only critical point.

19. mathcalculus

just plug into original function?

20. mathcalculus

yes but it has to be written as a point @abb0t

21. abb0t

Yes, plug it into original.