To simplify the expression (81x^-16 y^-28)^1/4 to the simplest form using only positive exponents, we can apply the rules of exponents.
Let's break down the steps:
Step 1: Distribute the exponent to each term inside the parentheses:
(81^(1/4) * x^(-16/4) * y^(-28/4))
Step 2: Simplify each term:
(3 * x^(-4) * y^(-7))
Step 3: Rewrite negative exponents as positive exponents:
(3 / x^4 * 1 / y^7)
Step 4: Combine the terms:
3 / (x^4 * y^7)
In summary, the simplified form of the expression (81x^-16 y^-28)^1/4, using only positive exponents, is 3 / (x^4 * y^7).