jing_koo
幼苗
共回答了15个问题采纳率:93.3% 举报
[(x^2-6x+9)/(2x-6)]*(x+3)
=[(x-3)^2/2(x-3)]*(x+3)
=(x-3)(x+3)/2
=(x^2-9)/2
=(5-9)/2
=-2
[(3x-1)/(x^2-1)]/[(3x/(x+1)]-1/(x-1)
=(3x-1)(x+1)/[3x(x^2-1)]-1/(x-1)
=(3x-1)(x+1)/[3x(x+1)(x-1)]-1/(x-1)
=(3x-1)/[3x(x-1)]-3x/[3x(x-1)]
=(3x-1-3x)/[(3x(x-1)]
=-1/[(3x(x-1)]
=-1/[3*2*(2-1)]
=-1/6
1年前
8