Doublecheck reduction of rational expressions

[late347]

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##

 

[Mark44]

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.

 

[late347]

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.