how do we evaluate a fraction being raised to negative exponents ?
example: (a/b)^-n <--- how do we change the exponent power to a positive number? I need the steps, :D
Thanks in advance,
Regards,
Anonymous :P
Try looking through this post - it will help
http://web2.0calc.com/questions/indices-especially-negative-indices
Just "flip" the fraction over and change the exponent to a positive...to see why this is so, consider......
(2/3)-3 = 1/(2/3)3 = 1/(8/27) = (27/8) = (3/2)3...........voila !!!!
how do we evaluate a fraction being raised to negative exponents ?
$$\left(\dfrac{a}{b}\right)^{-n}
\\\\=
\dfrac{a^{-n}} {b^{-n}}
\\\\=
\dfrac{a^{-n}} {1}
*
\dfrac{1} {b^{-n}}
\\\\=
\dfrac{1} {a^n}
*
\dfrac{b^n } {1}
\\\\=
\dfrac{b^n} {a^n}
\\\\=
\left(\dfrac{b}{a}\right)^n
\\\\
\boxed{\left(\dfrac{a}{b}\right)^{-n}=\left(\dfrac{b}{a}\right)^n }$$
Try looking through this post - it will help
http://web2.0calc.com/questions/indices-especially-negative-indices