# Simplify:  (y^x times y^-x)^4 Remove the negative exponent in the numerator by rewriting `y^-x`  as `1/(y^x)`  A negative exponent follows the rule: `a^(-n) = 1/a^n` `(y^x * 1/(y^x))^4` Multiply `y^x`  by `1/(y^x)`  to get `(y^x)/(y^x)` `((y^x)/(y^x))^4` Reduce the exponents of `y` by subtracting the denominatorexponents from the numeratorexponents. `(y^(x - (x)))^4` Simplify...

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Remove the negative exponent in the numerator by rewriting `y^-x`  as `1/(y^x)`  A negative exponent follows the rule: `a^(-n) = 1/a^n`

`(y^x * 1/(y^x))^4`

Multiply `y^x`  by `1/(y^x)`  to get `(y^x)/(y^x)`

`((y^x)/(y^x))^4`

Reduce the exponents of `y` by subtracting the denominator exponents from the numerator exponents.

`(y^(x - (x)))^4`

Simplify the exponent of `y` .

`(y^0)^4`

Expand the exponent `(4)` to the expression.

Therefore, `(y^x * y^-x)^4 =1`

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