what is the product of (5^-1)(5^-3) ; what is the difference x/x^2-16 - 3/x-4; which expression is equivalent to 5 2 5 1; which expression is equivalent to 3x^-6y^-3/15x^2y^10; what is the solution to the equation y/y-4-4y+4=32/y^2-16; what is the product 4n/4n-4 * n-1/n+1; which expression is equivalent to (4x^3)(2x)^-4; which graph represents the function f(x)=4/x