若方程k/(x+1)+3/(x-1)=7(x²;-1)無解,則k=

若方程k/(x+1)+3/(x-1)=7(x²;-1)無解,則k=

解由k/(x+1)+3/(x-1)=7/(x²;-1)
即k(x-1)+3(x+1)=7
由方程無解,即x=1或x=-1
當x=1時,k不存在
當x=-1時,即-2k=7,即k=-7/2.
即k=-7/2