Which expression is equivalent to #5^-8*5^3#?

1 Answer
Dec 9, 2016

#5^-5# or #1/5^5# or #1/3125#

Explanation:

Using the rules for exponents (#color(red)(x^a*x^b = x^(a+b))#):

#5^-8*5^3 -> 5^(-8+3) -> 5^-5#

We can convert further using another rule for exponents (#color(red)(x^-a = 1/x^-a)#):

#5^-5 -> 1/5^5#

And then converting the exponent to a number gives:

#1/(5*5*5*5*5) -> 1/3125#