狂野细辉
幼苗
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x+y+z = a*10^(n-1) + b*10^n + c*10^(n+1)
= 10^(n-1) [ a + 10b + 100c ]
根据科学记数法的性质,可知
a,b,c ∈ [1,10)
∴a + 10b + 100c ∈ (100,1110)
当 a + 10b + 100c ∈ (100,1000)时
即,(a + 10b + 100c) / 100 ∈ (1,10)
x+y+z = (a +10b +100c) (1/100) *100 ×10^(n-1) = (a +10b +100c) (1/100) × 10^(n+1)
即,x+y+z的科学记数法形式为:(a +10b +100c) (1/100) × 10^(n+1)
当 a + 10b + 100c ∈ [1000,1110)时,
即,(a + 10b + 100c) / 1000 ∈ [1,1.1)
x+y+z = (a +10b +100c) (1/1000) *1000 ×10^(n-1) = (a +10b +100c) (1/1000) × 10^(n+2)
即,x+y+z的科学记数法形式为:(a +10b +100c) (1/1000) × 10^(n+2)
1年前
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