Scientific Notation (Jump to: Lecture | Video )

0.00000000018

How could we express the above number in scientific notation?

Figure 1.

First, move the decimal point until it includes the first significant digit. Next, count how many places the decimal point was moved.

Here, we moved the decimal point 10 places to the right. Expressed in scientific notation, we have 1.8 * 10^(-10). The exponent is negative because the decimal was moved to the right. If it were moved to the left, the exponent would have been positive.

Let's try to go in the other direction. How would you write the below expression in standard notation?

Figure 2.

Because it's to the positive 4th power (and we're now going backwards), we move the decimal point four places to the right:

Figure 3.