### The Maxima on-line user's manual

Algebra Calculator

#### Xthru

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.

Sometimes it is better to use `xthru` before `ratsimp`ing 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 `ratsimp`ed.

```          (%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) ```

### Related Examples

##### xthru

(1-(x2+dx2)^2-(x1+dx1...

xthru(%);

Calculate

##### xthru

xthru((2+a) / (6 * a ...

xthru((8*r - 8*s)/(...

Calculate

##### xthru

f:24*Dwi_x[t+1]*V[t+1...

K:1/((13+11*Dwi_x[t+1...

NR1_NET:K*Dwi_x[t+1]/...

Calculate

##### xthru

eq1: (e1+e2+2*(e3+e4)...

xthru(eq1);

Calculate

##### xthru

(1-(x2+dx2)^2-(x1+dx1...

xthru(%);

Calculate

##### xthru

((x*2)^20 - 2*y)/(x*y...

xthru (%);

Calculate

##### xthru

f:24*Dwi_x[t+1]*V[t+1...

K:1/((13+11*Dwi_x[t+1...

NR1_NET:K*Dwi_x[t+1]/...

Calculate

##### xthru

((x*2)^20 - 2*y)/(x*y...

xthru (((x*2)^20 - 2...

Calculate

##### xthru

f:24*Dwi_x[t+1]*V[t+1...

K:1/((13+11*Dwi_x[t+1...

NR1_NET:K*Dwi_x[t+1]/...

Calculate

##### xthru

xthru((2+a) / (6 * a ...

Calculate