8 books with 2 sheets each and 1 extra sheet as leftover
On't want to be ripped off do you?/ That's why you want to have some interest. Just in a simple form this is a rush job right now.
I suppose

The vectors that span
form a basis for
if they are (1) linearly independent and (2) any vector in
can be expressed as a linear combination of those vectors (i.e. they span
).
Compute the Wronskian determinant:

The determinant is non-zero, so the vectors are linearly independent. For this reason, we also know the dimension of
is 3.
Write an arbitrary vector in
as
. Then the given vectors span
if there is always a choice of scalars
such that

which is equivalent to the system

The coefficient matrix is non-singular, so it has an inverse. Multiplying both sides by that inverse gives

so the vectors do span
.
The vectors comprising
form a basis for it because they are linearly independent.
First align the decimal points and the numbers, then add the extra 0's if needed. Lastly, add and the total answer is 14.225.