
Cristian M. answered 08/01/20
Researcher and Analyst Offers Patient and Clear Tutoring
Question: If a=2, b=3, and c=5, evaluate the following. Give your answer as an integer, fraction, or decimal rounded to at least 4 places.
ln(a1/b3c-1)
Answer: Remember the rules of working with logarithms.
Let's take care of a big part first. Remember the Quotient Rule: ln(x/y) = ln(x) - ln(y)
ln(a1/b3c-1) = ln(a1) - ln(b3c-1)
Let's take care of another big part. Remember the Product Rule: ln(x*y) = ln(x) + ln(y)
ln(b3c-1) = ln(b3) + ln(c-1)
So now we have this expansion:
ln(a1/b3c-1) = ln(a1) - [ ln(b3) + ln(c-1) ]
Let's make some substitutions:
ln((2)1) - [ ln((3)3) + ln((5)-1) ]
Simplify. You will use the same rules as above, but in reverse, so please get to know them! They will be your best friend moving forward in math!
ln(2) - [ ln(27) + ln(1/5)]
ln(2) - [ ln(27*(1/5)) ]
ln(2) - ln(27/5)
ln( 2 / (27/5) )
ln(10/27)
So ln(10/27) is an exact final answer, but let's turn it into a decimal number rounded to four places.
Since the argument for the natural log is a fraction between 0 and 1, I expect the final number to be negative.
ln(10/27) ≈ -0.9933