Answer
$\displaystyle \frac{2}{3}\cdot x^{1.2}-\frac{1}{3}\cdot x^{2.1}$
Work Step by Step
An expression is in exponent form if
* there are no radicals and
* all powers of unknowns occur in the numerator.
All terms in a sum or difference are of the form:
(constant)(expression with x$)^{p}$
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For the first term (x in the denominator) we use
$a^{-n}=\displaystyle \frac{1}{a^{n}}=(\frac{1}{a})^{n}$
so $\displaystyle \frac{2}{3x^{-1,2}}$ becomes $\displaystyle \frac{2}{3}x^{-(-1.2)}=\frac{2}{3}\cdot x^{1.2}$
the second term is $\displaystyle \frac{1}{3}\cdot x^{2.1}$
The expression, in exponent form is
$\displaystyle \frac{2}{3}\cdot x^{1.2}-\frac{1}{3}\cdot x^{2.1}$
