Saturday

February 28, 2015

February 28, 2015

Posted by **Alex** on Monday, January 3, 2011 at 5:57pm.

- info needed -
**MathMate**, Monday, January 3, 2011 at 6:02pmIt would help if you would describe how the lines are drawn.

- Calculus -
**Alex**, Monday, January 3, 2011 at 7:04pmit is a rectangle with a shaded square in the top left and bottom left corners.....there is a shaded rectangle in the top right corner and bottom right corner....there is a shaded square to the left of the rectangle in the top right corner and the bottom right corner....in between the two shaded squares is an unshaded rectangle, both top and bottom....there are 2 horizonal lines that split the rectangle in 3 parts and there are 4 vertical lines that split the rectangle into four parts.

- Calculus -
**MathMate**, Monday, January 3, 2011 at 8:37pmIf you name the sides of the squares as of length x, then the horizontal rectangles are 30-x long, and the vertical ones are 30-2x long.

The total volume is therefore

A(x)=x(30-x)(30-2x)

which is a function of a single variable x.

Find the derivative of A(x) as A'(X) and equate A'(x)=0 to find the maximum area.

There will be two roots, x1 and x2. To distinguish the maximum from the minimum, we calculate A"(x) (second derivative of A(x)).

If A"(x)>0, it is a minimum.

If A"(x)<0, it is a maximum.

You will find that the smaller root is the maximum and equal to about 6.34, and the corresponding maximum volume is about 2598 in³.

**Answer this Question**

**Related Questions**

Calculus - You are given a 60 inch by 30 inch piece of cardboad and asked to ...

algebra - I have a piece of cardboard that is twice as long as it is wide .I f I...

Calculus - From each corner of a square piece of cardboard, remove a square of ...

Math - From a 10-inch-by-19-inch piece of cardboard, 3-inch-square corners are ...

Math - An open box is to be made from a 11 inch by 11 inch piece of cardboad. ...

calculus - An open box is to be made out of a 8-inch by 14-inch piece of ...

Algebra - A box with a lid is to be cut out of a 12 inch by 24 inch sheet of ...

MATH help - A box with no top is to be constructed from a piece of cardboard ...

Algebra - You have to make a square-bottomed, unlidded box with a height of ...

Calculus - An open top box is made by cutting congruent squares from the corners...