How do you simplify [x^-9(81x^8)]^(5/4)?

1 Answer
Apr 25, 2017

=243/(x^(5/4)) = 243/(root4 x^5)

Explanation:

Use the power law of indices - multiply the indices.

[x^-9(81x^8)]^(5/4) " = "x^(-45/4) xx81^(5/4)x^10

Recall: color(red)(x^m xx x^n = x^(m+n))" and "color(blue)(x^(p/q) = rootq x^p)

color(red)(x^(-45/4)) xxcolor(blue)(81^(5/4))color(red)(x^10) = color(blue)(root4(81)^5)color(red)(x^(-5/4))

Recall: x^-m = 1/x^m

=color(blue)(3^5)/color(red)(x^(5/4))

=243/(x^(5/4))