| 部分分数表示して; -1 + 1/(-1 + x)^2 - 1/(-1 + x) + x
In[2]:= D[-1 + 1/(-1 + x)^2 - 1/(-1 + x) + x, x] Together[%] Solve[% == 0, x]
Out[2]= 1 - 2/(-1 + x)^3 + 1/(-1 + x)^2
Out[3]= (-4 + 4*x - 3*x^2 + x^3)/(-1 + x)^3
Out[4]= {{x -> 2}, {x -> 1/2*(1 - I*Sqrt[7])}, {x -> 1/2*(1 + I*Sqrt[7])}} --------------------------------------------- In[5]:= D[-1 + 1/(-1 + x)^2 - 1/(-1 + x) + x, {x, 2}] Together[%] Solve[% == 0, x]
Out[5]= 6/(-1 + x)^4 - 2/(-1 + x)^3
Out[6]= -((2*(-4 + x))/(-1 + x)^4)
Out[7]= {{x -> 4}}
|