Identify components: Identify the components of the function. The function f(x)=−(x+2)2+16 is a quadratic function shifted and reflected. We will use the power rule and chain rule to find the derivative.
Apply rules: Apply the power rule and chain rule. The power rule states that the derivative of xn is n∗x(n−1). The chain rule allows us to differentiate composite functions.
Differentiate squared term: Differentiate the squared term. The derivative of (x+2)2 with respect to x is 2⋅(x+2)2−1⋅dxd(x+2) by the power rule and chain rule.
Calculate inner function: Calculate the derivative of the inner function. The derivative of x+2 with respect to x is 1.
Combine results: Combine the results. Multiplying the derivative of the outer function by the derivative of the inner function gives us 2∗(x+2)∗1.
Apply rules: Apply the negative sign and constant rule. The derivative of a constant is 0, so the derivative of +16 is 0. The negative sign in front of the squared term applies to the derivative, so we have −2∗(x+2).
Simplify derivative: Simplify the derivative. The derivative of f(x)=−(x+2)2+16 is f′(x)=−2⋅(x+2)⋅1+0, which simplifies to f′(x)=−2x−4.
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