Doublecheck reduction of rational expressions

AI Thread Summary
The discussion centers on the reduction of the rational expression ##\frac{(\frac{1}{a})^2*b^{-3}}{ab^3}##. The user initially calculated the result as ##\frac{1}{a^3b^6}##, while the teacher provided a different answer, ##\frac{1}{a^2b^6}##. Upon review, it was determined that the teacher likely made a mistake due to rushed calculations and a typo. The user confirms their solution is correct and emphasizes the importance of starting with the same expression. This highlights the need for careful verification in mathematical problem-solving.
late347
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Homework Statement


teacher gave me the correct solution which said that the result from him was as follows
##\frac{1}{a^2b^6}##

Homework Equations



original problem was as follows
##\frac{ (\frac{1}{a})^2*b^{-3}}{ ab^3 }##

The Attempt at a Solution



[/B]##\frac{\frac{1}{(a^2)b^3}}{ab^3}##

##= (\frac{1}{a^2b^3}) / (\frac{ab^3}{1})##

##= (\frac{1}{a^2b^3}) * \frac{1}{ab^3}##

##=\frac{1}{a^2b^3} ~~* ~~\frac{1}{a^1b^3}##

##=\frac{1}{a^3b^6}##

notice how there is the denominator ##a^3b^6##
 
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late347 said:

Homework Statement


teacher gave me the correct solution which said that the result from him was as follows
##\frac{1}{a^2b^6}##

Homework Equations



original problem was as follows
##\frac{ (\frac{1}{a})^2*b^{-3}}{ ab^3 }##

The Attempt at a Solution



[/B]##\frac{\frac{1}{(a^2)b^3}}{ab^3}##

##= (\frac{1}{a^2b^3}) / (\frac{ab^3}{1})##

##= (\frac{1}{a^2b^3}) * \frac{1}{ab^3}##

##=\frac{1}{a^2b^3} ~~* ~~\frac{1}{a^1b^3}##

##=\frac{1}{a^3b^6}##

notice how there is the denominator ##a^3b^6##
I agree with your answer, not your teacher's. Make sure that you and the teacher are both starting with the same expression.
 
Mark44 said:
I agree with your answer, not your teacher's. Make sure that you and the teacher are both starting with the same expression.
yep on closer inspection... it looks like my teacher simply used rushed calculation, doing several things at the same time... and he made a typo because of that.

it look like he had a correct mid-result from an earlier calculation but forgot about it.
 

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