Apiece of cardboard measures 10 ft by 10 ft. four equal squares of size x are removed from the corners. after removing the squares, the piece of cardboard is then folded into an open top box. what value of x would maximize its volume?

The value of x would be

Step-by-step explanation:

Given,

The dimension of the cardboard = 10 ft by 10 ft,

∵ After removing four equal squares of size x ( in ft ) from the corners,

The dimension of the resultant box would be,

Length = ( 10 - 2x ) ft,

Width = ( 10 - 2x ) ft,

Height = x ft,

The volume of box,

Differentiating with respect to x,

Again differentiating with respect to x,

For maxima or minima,

By quadratic formula,

For x = 5/3, V'' = negative,

While for x = 5, V'' = Positive,

Hence, the value of x would be 5/3 ft for maximising the volume.

b) yes

step-by-step explanation:

let the statements be named as,

statement 1: if the power has been cut, then the refrigerator does not work.

statement 2: the refrigerator does not work.

conclusion: the power has been cut

now, 'law of detachment states that if we have the statements given as,

1. if p, then q.

2. p

then, we get the true statement or conclusion as q'.

thus, on comparing, we get that,

p: if the power has been cut.

q: the refrigerator does not work.

so, the argument is true by the law of detachment.