先化简,再求值:x+3/x+2除以(x-2-[5/x+2})

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先化简,再求值:x+3/x+2除以(x-2-[5/x+2})
先化简,再求值:x+3/x+2除以(x-2-[5/x+2})

先化简,再求值:x+3/x+2除以(x-2-[5/x+2})
=(x+3)/(x+2)÷(x²-4-5)/(x+2)
=(x+3)/(x+2)×(x+2)/(x+3)(x-3)
=1/(x-3)

x+3/x+2除以(x-2-[5/x+2})
=(x+3)/(x+2)÷[(x^2-4-5)/(x+2)]
=(x+3)/(x+2)*(x+2)/【(x+3)(x-3)】
=1/(x-3)

x=4时
1/(x-3)=1