[Sowya] 多项式的运算仍需加强
>> x-(1|5x+( -6|5x^3-6|5x^2-4|5x+2)/(5x^4-9x^2-4x^1-1))
in> x-(1|5x+(-6|5x^3-6|5x^2-4|5x+2)/(5x^4-9x^2-4x^1-1))
out> 4|5x^1
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这显然是不对的.
>> x^2/(x^3+x^2)
in> x^2/(x^3+x^2)
out>
quotient> q(x) = 0
remainder> r(x) = x^2
0
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需要加入一元多项式因式分解的功能, 才能使得除法得以化简.