Identify Function: Identify the function whose derivative we need to find.The function is f(x)=x, which can also be written as f(x)=x(1/2).
Apply Power Rule: Apply the power rule for differentiation to find the derivative of f(x)=x21. The power rule states that if f(x)=xn, then f′(x)=n⋅xn−1. Using this rule, the derivative of f(x)=x21 is f′(x)=21⋅x(21−1)=21⋅x−21.
Simplify Derivative: Simplify the expression for the derivative. f′(x)=21x−21 can be rewritten as f′(x)=21(x1).
Evaluate at x=9: Evaluate the derivative at x=9.Substitute x with 9 in the expression f′(x)=21⋅x1.f′(9)=21⋅91=21⋅31=61.
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