先化简再求值:[(2x+6)/(x^2-4x+4)]÷(x+3)×[(x-2)/(x+3)],其中x=3

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先化简再求值:[(2x+6)/(x^2-4x+4)]÷(x+3)×[(x-2)/(x+3)],其中x=3
先化简再求值:[(2x+6)/(x^2-4x+4)]÷(x+3)×[(x-2)/(x+3)],其中x=3

先化简再求值:[(2x+6)/(x^2-4x+4)]÷(x+3)×[(x-2)/(x+3)],其中x=3
原式=2(x+3)/(x-2)²*1/(x+3)*(x-2)/(x+3)
=2/(x-2)²*(x-2)/(x+3)
=2/(x-2)(x+3)
=2/(1*6)
=1/3

[(2x+6)/(x^2-4x+4)]÷(x+3)×[(x-2)/(x+3)]
=2[(x+3)/(x-2)^2]*[1/(x+3)]*[(x-2)/(x+3)]
=[2/(x-2)^2]*[(x-2)/(x+3)]
=2/[(x-2)(x+3)]
x=3,原式=2/[(3-2)*(3+3)]=1/3

原式=[2(x+3)/(x-2)²]*1/(x+3)* [(x-2)/x(x+3)]
=2/[(x-2)(x+3)]
x=3
原式=2/(3-2)(3+3)
= 1/3