vì (|..................................)=0 mà |x-2013|+2014>0;x^2+5>0 Nên 9-x^2=0=>x=3

cám ơn nha . cho bạn nhá

1)-hinh dang:hinh cau,hinh que,hinh dau phay,hinh xoan,...

-kich thuoc:rat nho.

-cau tao:gom nhung don bao rieng le hoac xep thanh tung chuoi, tung dam,...

2)-co 2 cach:-di duong,tu duong.

-di duong:hoai sinh, ki sinh.

-vi khuan co nhieu cach dinh duong khac nhau, mot so vi khuan co the che tao chat huu co de song do la vi khuan tu duong.

-phan lon vi khuan song nho vao chat huu co co san goi la vi khuan di duong.

-vi khuan ki sinh la vi khuan song bam dua vao chat huu co cua co the song khac.

-vi khuan hoai sinh la vi khuan song nho vao su phan giai chat huu co co san(xac dong-thuc vat...).

3)D

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