factor over complex numbers?

Hi Milan,

>> Is there any option I can set to get factor(expr1) -> (-%i + x)^5  (%i +
>> x)^5
>> instead of getting (1 + x^2)^5 ?
>>

>factor(expr1,x^2+1);

>Milan

I get factor(expr1,x^2+1);  --> 0

ted
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(%i1) display2d:false$
(%i2) expr1 : expand( (1+x^2)^5 );
(%o2) x^10+5*x^8+10*x^6+10*x^4+5*x^2+1

(%i3) factor( expr1 );
(%o3) (x^2+1)^5

(%i4) gfactor( expr1 );
(%o4) (x-%i)^5*(x+%i)^5

(%i5) factor( expr1, x^2 + 1 );
(%o5) 0
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