Answer
$x$
Work Step by Step
RECALL:
(i) $a^{-m} = \dfrac{1}{a^m},a\ne0$
(ii) $\sqrt[n]{a^m} = a^{\frac{m}{n}}$
(iii) $\dfrac{a^m}{a^n} = a^{m-n}, a\ne0$
Use rule (ii) above to obtain:
$=\dfrac{x^{\frac{7}{4}}}{x^{\frac{3}{4}}}$
Use rule (iii) above to to obtain:
$=x^{\frac{7}{4} - \frac{3}{4}}
\\=x^{\frac{4}{4}}
\\=x^1
\\=x$
