Question

（（xy+2）（xy-2）-2x^2y^2+4)除以xy,其中x=10,y=-1/5

（（xy+2）（xy-2）-2x^2 y^2+4)化简求值

Answer 1

你好，love厨子

[(xy+2)(xy-2)-2x²y²+4]÷(xy)
=[x²y²-4-2x²y²+4]÷(xy)
=(-x²y²)÷(xy)
=-xy
∴当x=10，y=-1/5时，
原式=-[10×(-1/5)]=2

Answer 2

原式=(x^2y^2-4-2x^2y^2+4)÷xy
=-x^2y^2÷xy
=-xy
=2