Online Algebra Calculator
Many of users do not use powerful Maxima computer algebra system for systematic work, but for ad hoc algebraic calculations – equations, functions, matrixes, etc. only. To do this job, it is not useful to download the whole application from a web site.
Function: xthru (<expr>) Combines all terms of <expr> (which should be a sum) over a common denominator without expanding products and exponentiated sums as ratsimp does. xthru cancels common factors in the numerator and denominator of rational expressions but only if the factors are explicit.
![Xthru Example f(x):= x*log(x)+(x-1)*exp(1)/(exp(1)-1);
f(1);
f(2);
diff(f(x),x);
xthru(expand(xthru(diff(f(x),x))));
solve(diff(f(x),x),x);
plot2d(f(x),[x,1,5]);](http://maxima-online.org//plot.html?g=p396271618.png&t=img&db=r-485819712)
Sometimes it is better to use xthru before ratsimping an expression in order to cause explicit factors of the gcd of the numerator and denominator to be canceled thus simplifying the expression to be ratsimped.
(%i1) ((x+2)^20 - 2*y)/(x+y)^20 + (x+y)^(-19) - x/(x+y)^20;
20
1 (x + 2) - 2 y x
(%o1) --------- + --------------- - ---------
19 20 20
(y + x) (y + x) (y + x)
(%i2) xthru (%);
20
(x + 2) - y
(%o2) -------------
20
(y + x)(%o1) true (%i2)