先化简:(a-2)/(a^2-4)+1/(a+2),化简后请你为a选择一个适当的数代入求值.

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先化简:(a-2)/(a^2-4)+1/(a+2),化简后请你为a选择一个适当的数代入求值.
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先化简:(a-2)/(a^2-4)+1/(a+2),化简后请你为a选择一个适当的数代入求值.
先化简:(a-2)/(a^2-4)+1/(a+2),化简后请你为a选择一个适当的数代入求值.

先化简:(a-2)/(a^2-4)+1/(a+2),化简后请你为a选择一个适当的数代入求值.

原式=(a-2)/(2(a-2))+1/(a+2)=1/2+1/(a+2) (a不等于2且a不等于-2)
a=3时,原式=1/2+1/(3+2)=5/10+2/10=7/10

原式=(a-2)/[(a+2)(a-2)]+1/(a+2)=1/(a+2)+1/(a+2)=2/(a+2)
当a=0时,原式=(-2)/(-4)+1/(2=1/2+1/2=2/2=1

(a-2)/(a^2-4)+1/(a+2)=(a-2)/((a-2)(a+2))+1/(a+2)=1/(a+2)+1/(a+2)=2/(a+2)
当a=2时,原式=1/2