How do you evaluate #(3\times 10^ { 8} ) ( 3\times 10^ { - 12} )#?

1 Answer
Oct 30, 2017

#=0.0009#

Explanation:

#(3\times 10^ { 8} ) ( 3\times 10^ { - 12} )#
As there is no plus or minus operator, it can be written as:

#=>3\times 10^ { 8} xx 3\times 10^ { - 12} #

Use rule of indices: # a^m xx a^n = a^(m+n)#

#=>3\times 3xx 10^ { 8 - 12} #

#=> 3^2 xx 10 ^-4 = 9xx10^-4#

Use rule of indices: #a^-m= 1/a^m#

#=> 9/ 10^4#

#=> 9/10000 = 0.0009#