化简：[3/(a+1)-a+1]／[(a²－4a+4)／(a+1)]

[a/(a-1)+a/(a+2)](a+2)/(2a平方+3a+1)化简 化简3a×a×a+12a×a-6a-12 a=根号7-1 化简:-a+a/a+1 a*a*a*a+a*a+1/a*a+a+1 化简 (a 1)(a 2)(a 3)(a (a+2)(a+1)-a(a-3) (1+a)(1-a)-a(a-3) 化简 化简(a+1)(a-2)/(a+2)(a-2)+3 化简 3a-[5a-(a+2)+a]-1 化简：a(a*a-1)+2a*a(a+1)-3a(2a-5)拜托了各位 化简1/(a+1)(a+2)+1/(a+2)(a+3)+...+1/(a+2010)(a+2011) 化简:(a^3-a^2-a+1)/(a^3-3a^2+3a-1) (a^3 - a^2 - a + 1)/(a^3 - 3a^2 + 3a - 1) 化简. (3a/a+1 - a/a-1)除a/a平方-1 化简 化简：a³-a²-a+1/a³-3a²+3a-1 化简(a+ 3)(a-3) (a-5)(a+7)-2a(a-1) 化简2a(a·a-3a-1)a乘a (a-1)(a-3)