1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=1/(x+4)
解方程:1/x2+x +1/x2+3x+2 +1/x2+5x+6 +1/x2+7x+12 +1/x2+9x+20=5/x
1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=1/(x+4)
1/(x2+x)+1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)=4/21
(x2+3x+9)/(x2-27)+(6x)/(9x-x2)-(x-1)/(6+2x)
先化解,再求值:【1/(x2+3x+2)+1/(x2+5x+6)+1/(x2+7x+12)】/1/(x2+9x+20),
解方程:X2--1/8(X2+2X)+X2+2X/3(X2--1)=11
解方程 x2+x-1/(x2+x)=3/2
(x2+5x+4)2+2(x2+5x+4)2+1=(x2+.
解方程7/(x+x2)-3/(x-x2)=6/(x2-1)
解方程 2/(x2-x)+6/(1-x2)=7/(x2+x)
解方程2/x2+x+3/x2-x=4/x2-1
1/x2-3x+2+1/x2-5x+6+1/x2-7+1/x2-7x+12-4/x2-6x+5 有多少种写多少种解法,