## Ephilo help please ? find the critical numbers of f,describe the open intervals on which f is increasing or decreasing locate all relative extrema one year ago one year ago

1. Best_Mathematician

calculus...? whats the equation

2. Ephilo

|dw:1363827249708:dw|

3. Best_Mathematician

critical numbers are when derivative equals zero....right?

4. Ephilo

@Best_Mathematician yes

5. Best_Mathematician

so the derivative is |dw:1363827381385:dw|

6. Best_Mathematician

set it equal to zero and find value of x

7. satellite73

not to butt in, but you certainly don't need calculus for this it is a quadratic, therefore a parabola the leading coefficient is positive, so it open up the first coordinate of the vertex is $$-4$$ so it decrease on $$(-\infty, -4)$$ and increases on $$(-4,\infty)$$

8. Lena772

@satellite73 is there any relative extrema here?