I need this question solved with derivatives please: A rectangular piece of cardboard, 100 cm by 40 cm, is going to be used to
make a rectangular box with an open top by cutting congruent squares from
the corners. Calculate the dimensions (to one decimal place) for a box with
the largest volume.

16,242. 7 cm^3.

Step-by-step explanation:

We need to cut off a square piece at the 4 corners of the cardboard.

Let the length of their edges be x cm.

The volume of the box will be:

V = height * width * length

V = x(100-2x)(40-2x)

V = x(4000 - 200x - 80x + 4x^2)

V = x(4x^2 - 280x + 4000)

V =  4x^3 + - 280x^2 + 4000x

Finding the derivative:

dV / dx =  12x^2 - 560x + 4000  = 0  ( when  V is a maxm or minm.)

4(3x^2 - 140x + 1000) = 0

x =  37.86, 8.80.

Looks like x = 8.80 is the right value but we can check this out be looking at the sign of the second derivative:

V" =  24x - 560, when x = 8.8   V" is negative so this is a Maximum for V.

So the maximum volume of the box is when x = 8.8 so we have

V =  8.8(100-2(8.8)(40 - 2(8.8)

=  16,242. 7 cm^3.

56

step-by-step explanation:

the length of o'p' is .

step-by-step explanation:

it is given that the quadrilateral m'n'o'p' is the image of quadrilateral mnop after dilation.

the center of dilation is origin and the scale factor is 1.5.

in dilation the image and preimge are similar figures. it means the sides of image and preimage are proportional.

the scale factor is defined as

the scale factor is 1.5.

multiply both sides by op.

note: if the value of op is given, then multiply the value of op with 1.5 to get the length of side o'p'.

therefore length of o'p' is .