Identify Function and Point: Identify the function and the point at which the derivative is to be evaluated.We are given the function f(x)=x21 and we need to find its derivative at the point x=4.
Differentiate with Power Rule: Differentiate the function with respect to x. To find f′(x), we use the power rule for differentiation, which states that if f(x)=xn, then f′(x)=n⋅x(n−1). Differentiating f(x)=x(1/2), we get f′(x)=(1/2)⋅x((1/2)−1)=(1/2)⋅x(−1/2).
Simplify Derivative Expression: Simplify the expression for the derivative.Simplifying f′(x)=(21)∗x(−21), we can write it as f′(x)=(21)∗(x(21)1) or f′(x)=2∗x1.
Evaluate at x=4: Evaluate the derivative at x=4.Substitute x=4 into the derivative f′(x)=2x1 to find f′(4).f′(4)=241=2⋅21=41.
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