来自韩广的问题
(1/a+1)-(a+3/a^2-1)*(a^2-2a+1/a^2+4a+3)
(1/a+1)-(a+3/a^2-1)*(a^2-2a+1/a^2+4a+3)
1回答
2020-05-0623:19
(1/a+1)-(a+3/a^2-1)*(a^2-2a+1/a^2+4a+3)
(1/a+1)-(a+3/a^2-1)*(a^2-2a+1/a^2+4a+3)
[1/(a+1)]-{(a+3)/[(a+1)(a-1)]}*{[(a-1)^2]/[(a+3)(a+4)}
=[1/(a+1)]-(a-1)/[(a+1)(a+4)]
=[(a+4)-(a-1)]/[(a+1)(a+4)]
5/[(a+1)(a+4)]