puzzle with bfloat and radcan



On 5/14/12 3:42 PM, Richard Fateman wrote:
> xnum :
> ((6-4*sqrt(2))*log(3-2*sqrt(2))+(3-2*sqrt(2))*log(17-12*sqrt(2))+32-24*sqrt(2));
> 
> xden :(48*sqrt(2)-72)*(log(sqrt(2)+1)+sqrt(2))/3;
> x    : xnum/xden;
> 

Can you get maxima to prove that x = 1?

I can get:

factor(expand(logcontract(gfactor(x))))
-> -(log(577-51*2^(7/2))-2^(7/2))/(log(51*2^(7/2)+577)+2^(7/2))

If I stare at it, I can see that the numerator and the denominator are
exactly the same except for the arg of the logs.  But a quick check
shows that 1/(51*2^(7/2)+577) = 577-51*2^(7/2), so, in fact, x = 1.

But how do I get maxima to do this for me, other doing what I described
above by hand?

I'm just curious.

Ray