Math Forum / Mathematics / Algebra Help / August 2004

I am not an algebra person....my daughter needs to know..,,if you have 3
dice totaling 6....how many times can you get the total 12? What is the
algorithm?

Sorry.....I worded the previous question wrong....
If you have 3 dice each has the numbers 1-6....how many times can you get
the total 12? What is the algorithm?

I'm trying to prove a few properties of additive inverses. It'd
be nice if someone can point errors, make
suggestions/corrections.
I must show that -(a - b) = -a + b.

In a book, I see the following proof:
Theorem: for each element of a ring R, it's true that
               x * 0 = 0 * x = 0
Proof:

I am desperate and don't know what to do.  I am disabled and confined to home.
I have Post-Polio Syndrome and Cancer.  I'm confined to a wheelchair.  A court
order has attached my Social Security Disability.  They took $510 of $920.  
In 1976 I was divorced.  I was paying support, ...

    I have been trying to prove this statement which seems
intuitively very obvious and which seems like it ought to be very
straightforward to prove, but which is actually turning out to be
quite hard...

Can someone tell me how to get ((k+1)(k+2)(2k+3))/6 out of (k(k+1)(2k+1))/6
+ (k+1)^2
Thanks!
Sven.

How would you work this problem out
0.021/2(1000 - 40)
my book has the answer as 24 but, how do you get that.
Also I think my book was wrong with this problem

I can calculate Wronskian for 2x2 matrix with no problems. But I have
no idea how to calcualte Wronskian for 3x3 matrix.
I found an example:
W(0) = (1 0 1)

one property is for sale for $1,285,000
it is 2258 sq.ft. of building(2story)
on a 1650 sq.ft. lot...
the man next door has a 600 sq.ft. building

Can anyone tell me why I received partial credit for the answer to this
question?  I just reviewing some test that I have taken last semester so I
can't ask my professor.
Given the functions f(x)= 3x^2 - 4x + 1 and g(x) = 9-2x,

I'm looking for Robert Blitzer's Instructor's Edition (0-13-660259-2)
and Instructor's Solutions Manual (0-13-746629-3)
for his College Algebra text.(Prentice-Hall)
if anyone has copies from with they'd like to part.

The question asks to find an equation of a plane containing points
<2,1,-1> (2,-5,3) and (4,0,3>
I got a u of <0,-6,4> and v of <2,-1,4>
with a final answer of -7.6 but I don't think this is correct.

I am trying to find the domain of this problem
1 / ( 4throot(x^2-5x) )
The denominator of a fraction must not equal 0 and the radicand must be a
positive number so:    x^2-5x >0

I am having a discussion with a collegue about a certain
exercise about a system of linear equations.  The question is:
"Suppose a non-homogenous system of 9 linear equations in 10 unknowns
has a solution for all possible right-hand sides.  Is it then possible