Apply the product rule to .

One to any power is one.

Move to the numerator using the negative exponent rule .

Create equivalent expressions in the equation that all have equal bases.

Since the bases are the same, then two expressions are only equal if the exponents are also equal.

Multiply each term in by .

Multiply .

Multiply by .

Multiply by .

Multiply by .

Solve for x (1/3)^x=81