1.因为(1/x)-(1/y)=3
所以y-x=3xy即x-y=-3xy
所以(2x-14xy-2y)/(x-2xy-y)=[2(x-y)-14xy]/[(x-y)-2xy]
=[-6xy-14xy]/[-3xy-2xy]
=4
2.因为x+(1/x)=2
所以x^2+1=2x
所以(x^2+2x+1)/(4x^2-7x+4)=[（x^2+1）+2x]/[4(x^2+1)-7x]
=(2x+2x)/(8x-7x)
=4