Scientific Notation
Key Questions
-
A number in scientific notation is in the form
#a * 10^b# To convert to a real number, write out
#a# then move the decimal point depending on#b# 's sign.If
#b# is positive, move the decimal point to the right
If#b# is negative, move the decimal point to the leftFor example,
#1.23 * 10^5# Moving the decimal point 5 places to the right, we have
#123000#
#4.56 * 10^-5# Moving the decimal point 5 places to the left, we have
#0.0000456# -
First, observe what happens when a particular number is multiplied or divided by multiples of 10.
#123.45 * 10 = 1234.5# Decimal place moved by 1 place to the right#123.45 * 100 = 12345# Decimal place moved by 2 places to the right#123.45 * 10000 = 1234500# Decimal place moved by 4 places to the right#67.89 * 1/10 = 6.789# Decimal place moved by 1 place to the left#67.89 * 1/100 = 0.6789# Decimal place moved by 2 places to the left#67.89 * 1/10000 = 0.6789# Decimal place moved by 4 places to the left
Remember that a number's multiples can also be expressed exponential form
#1 = 10^0#
#10 = 10^1#
#100 = 10^2#
#10000 = 10^4#
#1/10 = 10^-1#
#1/100 = 10^-2#
#1/10000 = 10^-4#
A number in scientific notation form is in the form
#A * 10^b# where
#A# is a rational number in decimal form.To convert to a number in scientific notation form,
move the decimal place by#b# places. If#b# is negative, move to the left. If#b# is positive, move to the right