Posted by **rachel** on Sunday, October 23, 2011 at 7:29pm.

im having so much trouble figuring out how to get these answers. i already know the answers i just need to figure out how to get them...

directions: find the points of inflection and discuss the concavity of the graph of the function...

1. f(x)=(1/2)x^4+2x^3

2. f(x)=x^3-6x^2+12x

3. f(x)=(1/4)x^4-2x^2

4. f(x)=2sinx+sin2x, [0,2ð)

- calculus -
**Steve**, Monday, October 24, 2011 at 12:36pm
1.

f = 1/2 x^4 + 2x^3

f' = 2x^3 + 6x^2

f'' = 6x^2 + 12x

f' = 0 at x=0,0,-3 so the possible mins/maxes are there

f'' = 0 at 0,-2 so the inflection is there.

At x=0, f'=0 and f''=0, so not a min/max -- inflection

At x=-3, y'' > 0, so concave up (min)

Proceed similarly with the others.

rechneronline . de is a good grapher

## Answer this Question

## Related Questions

- Math - I need help... I dont need the answer just how I would figure this out. ...
- calculus - Find any relative extrema and any points of inflection if they exist ...
- Calculus - Hi! I am having trouble figuring out the derivative of ln[sin^2(x)+3...
- math - use the method of cylindrical shells to find the volume generated by ...
- Geometry - The midpoint of line segment AB is (1,2). The coordinates of A are (-...
- Calculus - I am having a mental block. I have the answer to the question. It is...
- Calculus - 26. Find all points of inflection. f(x) = (5x-3)^(1/3) Note: I have ...
- Chemistry - I am having trouble getting this starting and figuring out the ...
- calculus - Sketch the curve y = x^3 - 12x^2 + 36x I already did the question ...
- Relative Extrema: AP Calculus - Consider the function f(x)= (3/4)x^4-x^3-3x^2+6x...

More Related Questions