把一個(gè)數(shù)寫(xiě)成a×10的n次方的形式(其中1≤|a|＜10,n為整數(shù)),
這種記數(shù)法稱(chēng)為科學(xué)記數(shù)法,其方法是(1)確定a,a是只有﹙﹚位整數(shù)的數(shù)；(2)確定n,當(dāng)原數(shù)的絕對(duì)值≥10時(shí),n為﹙﹚整數(shù),n等于原數(shù)的整數(shù)位數(shù)減﹙﹚；當(dāng)原數(shù)的絕對(duì)值＜1時(shí),n為﹙﹚整數(shù),n的絕對(duì)值等于原數(shù)中左起第一個(gè)非0數(shù)前0的個(gè)數(shù)(含整數(shù)位數(shù)上的0)