Identify Components: Identify the components of the function that will require the use of the product rule and the chain rule for differentiation. The function k(x)=−3x⋅e(−4x3+3x2) is a product of two functions, −3x and e(−4x3+3x2). The exponential function also contains a composite function, which will require the use of the chain rule.
Apply Product Rule: Apply the product rule for differentiation, which states that the derivative of a product of two functions is the derivative of the first function times the second function plus the first function times the derivative of the second function. Let u=−3x and v=e(−4x3+3x2). Then, k′(x)=u′v+uv′.
Differentiate u: Differentiate u=−3x with respect to x to get u′=−3.
Differentiate v: Differentiate v=e(−4x3+3x2) with respect to x using the chain rule. The chain rule states that the derivative of a composite function is the derivative of the outer function evaluated at the inner function times the derivative of the inner function. Let g(x)=−4x3+3x2 be the inner function. Then, v′=eg(x)⋅g′(x).
Differentiate g: Differentiate g(x)=−4x3+3x2 with respect to x to get g′(x)=−12x2+6x.
Substitute g′ into v′: Substitute g′(x) into the expression for v′ to get v′=e(−4x3+3x2)⋅(−12x2+6x).
Substitute into Product Rule: Substitute u′, v, and v′ into the product rule expression k′(x)=u′v+uv′ to get k′(x)=−3⋅e(−4x3+3x2)+(−3x)⋅(e(−4x3+3x2)⋅(−12x2+6x)).
Simplify Expression: Simplify the expression for k′(x) by distributing and combining like terms. k′(x)=−3e(−4x3+3x2)−3x⋅e(−4x3+3x2)⋅(−12x2+6x).
Factor out Common Factor: Factor out the common factor e(−4x3+3x2) to get k′(x)=e(−4x3+3x2)×(−3−3x×(−12x2+6x)).
Distribute −3x: Continue simplifying the expression by distributing −3x inside the parentheses. k′(x)=e(−4x3+3x2)⋅(−3+36x3−18x2).
Combine Like Terms: Combine like terms inside the parentheses to get the final expression for k′(x). k′(x)=e(−4x3+3x2)⋅(36x3−18x2−3).
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