当x=3时,求下列式子的值:3x+2/x平方-x-2+(1-1/x+1)÷(1+1/x-1)

问题描述:

当x=3时,求下列式子的值:3x+2/x平方-x-2+(1-1/x+1)÷(1+1/x-1)

原式=(3x+2)/(x-2)(x+1)+(x+1-1)/(x+1)÷(x-1+1)/(x-1)
=(3x+2)/(x-2)(x+1)+(x-1)/(x+1)
=(3x+2+x²-3x+2)/(x-2)(x+1)
=(x²+4)/(x-2)(x+1)
=(9+4)/(1*4)
=13/4