. . . .
(a) We have: . .
Square: . .
The volume is: .
Substitute  and : .
. . . . . . . . .
We have two equations to solve . . .
The diagram below shows a solid with volume V, obtained from a cube with edge
a > 1 when a smaller cube with edge 1/a is removed.
sorry for the image but there is not...so imagine a solid with an edge missing...so a small solid is missing on 1 edge..
Let x=a − 1/a
-Find V in terms of x
Hence or otherwise,show that the only value of a for whichV= 4x is a= 1+ √5 devided by 2..