科学记数法公式
在数学中，有大量的数字和数字图形。我们都熟悉数轴的概念，并且它无限延伸到零的左边和右边。结果，数字不断变得越来越小（向左）或越来越大（向右），以致于它们不再方便以十进制形式表示。这就是科学记数法概念出现的地方。下面讨论。
什么是科学记数法？
科学记数法是一种以更直接的方式显示极大或极小数字的方法。如上所述，数字可以无限扩展，但如此大的数字不能写在一张纸上。此外，要求小数点后百万位的数字以更直接的方式表示。因此，以扩展形式表示几个整数是具有挑战性的。因此，我们采用科学记数法。
简单地说，科学计数法用于将任何数字表示为十进制数，其值在 1 到 10 之间，不包括 10 乘以 10 的幂。科学计数法的一般形式是：
n × 10m
where,
n is a real number such that 1 ≤ n < 10 and is known as the significant.
科学记数法规则
- 科学计数法分为两部分：第一部分只是数字，小数点在第一位，第二部分是乘以 10 的小数点的幂数，将小数点放在它所属的位置。
- 如果给定的数字大于 1 且是 10 的倍数，则小数点必须向左移动，并且 10 的幂为正数。
示例：用科学计数法写 5890000。
解决方案：
Clearly the given number has only 3 considerable numbers/ figures since the zeroes are to be regarded as mere placeholders.
Following the first rule of scientific notation, put a decimal after the first digit in the given number.
5890000 = 5.89 × 100 × 10000
= 5.89 × 106
类似问题
问题 1. 用科学计数法写出 897,000,000,000。
解决方案：
Clearly the given number has only 3 considerable numbers/ figures since the zeroes are to be regarded as mere placeholders.
Following the first rule of scientific notation, put a decimal after the first digit in the given number.
897,000,000,000 = 8.97 × 100 × 1000000000
= 8.97 × 102 × 109
= 8.97 × 1011
问题 2. 用科学计数法写出 990000000000。
解决方案：
Clearly the given number has only 3 considerable numbers/ figures since the zeroes are to be regarded as mere placeholders.
Following the first rule of scientific notation, put a decimal after the first digit in the given number.
990000000000 = 9.9 × 10 × 10000000000
= 9.9 × 101 × 1010
= 9.9 × 1011
问题 3. 用科学计数法写出 0.00000077。
解决方案：
Move the decimal point up to 7 positions to the right of 0.00000077.
To make the number 7.7, the decimal point was moved 7 places to the right.
The decimal is moved to the right since the numbers are fewer than ten. As a result, we employ a negative exponent in this case.
⇒ 0.00000077 = 7.7 × 10-7
问题 4. 用科学计数法写出 0.0000426。
解决方案：
Move the decimal point up to 5 positions to the right of 0.0000426.
To make the number 4.26, the decimal point was moved 5 places to the right.
The decimal is moved to the right since the numbers are fewer than ten. As a result, we employ a negative exponent in this case.
⇒ 0.0000426 = 7.7 × 10-5
问题 5.用科学计数法写出 699000000。
解决方案：
Clearly the given number has only 3 considerable numbers/ figures since the zeroes are to be regarded as mere placeholders.
Following the first rule of scientific notation, put a decimal after the first digit in the given number.
699000000 = 6.99 × 100 × 1000000
= 6.99 × 102 × 106
⇒ 699000000 = 6.99 × 108
问题 6. 用科学计数法写出 358000000。
解决方案：
Clearly the given number has only 3 considerable numbers/ figures since the zeroes are to be regarded as mere placeholders.
Following the first rule of scientific notation, put a decimal after the first digit in the given number.
358000000 = 6.99 × 100 × 1000000
= 3.58 × 102 × 106
⇒ 358000000 = 3.58 × 108
问题 7. 将 0.00000055 转换为科学计数法。
解决方案：
Move the decimal point up to 7 positions to the right of 0.00000055.
To make the number 5.5, the decimal point was moved 7 places to the right.
The decimal is moved to the right since the numbers are fewer than ten. As a result, we employ a negative exponent in this case.
⇒ 0.00000055 = 5.5 × 10-7