Q. Given the function f(x)=(−4−6x3)(−9x3−4x2+5), find f′(x) in any form.Answer: f′(x)=
Apply Product Rule: To find the derivative of the function f(x)=(−4−6x3)(−9x3−4x2+5), we will use the product rule. The product rule 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.
Find Derivatives: Let's denote the first function as u(x)=−4−6x3 and the second function as v(x)=−9x3−4x2+5. We need to find the derivatives u′(x) and v′(x).
Distribute Terms: First, we find the derivative of u(x)=−4−6x3. The derivative of a constant is 0, and the derivative of −6x3 is −18x2. So, u′(x)=0−18x2=−18x2.
Simplify Expressions: Next, we find the derivative of v(x)=−9x3−4x2+5. The derivative of −9x3 is −27x2, the derivative of −4x2 is −8x, and the derivative of a constant is 0. So, v′(x)=−27x2−8x.
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.First, distribute −18x2 across the terms in the first parenthesis: f′(x)=(−18x2)(−9x3)+(−18x2)(−4x2)+(−18x2)(5).
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.First, distribute −18x2 across the terms in the first parenthesis: f′(x)=(−18x2)(−9x3)+(−18x2)(−4x2)+(−18x2)(5).Now, distribute −4 and −6x3 across the terms in the second parenthesis: f′(x)=f′(x)+(−4)(−27x2)+(−4)(−8x)+(−6x3)(−27x2)+(−6x3)(−8x).
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.First, distribute −18x2 across the terms in the first parenthesis: f′(x)=(−18x2)(−9x3)+(−18x2)(−4x2)+(−18x2)(5).Now, distribute −4 and −6x3 across the terms in the second parenthesis: f′(x)=f′(x)+(−4)(−27x2)+(−4)(−8x)+(−6x3)(−27x2)+(−6x3)(−8x).Let's simplify the terms we have so far: f′(x)=162x5+72x4−90x2+108x2+32x−162x5−48x4.
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.First, distribute −18x2 across the terms in the first parenthesis: f′(x)=(−18x2)(−9x3)+(−18x2)(−4x2)+(−18x2)(5).Now, distribute −4 and −6x3 across the terms in the second parenthesis: f′(x)=f′(x)+(−4)(−27x2)+(−4)(−8x)+(−6x3)(−27x2)+(−6x3)(−8x).Let's simplify the terms we have so far: f′(x)=162x5+72x4−90x2+108x2+32x−162x5−48x4.Combine like terms to get the final derivative: f′(x)=162x5−162x5+72x4−48x4−90x2+108x2+32x.
Combine Like Terms: Now we apply the product rule: f′(x)=u′(x)v(x)+u(x)v′(x). Substituting the derivatives we found, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x).We need to distribute the terms in the expression f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x). Let's do this step by step.First, distribute −18x2 across the terms in the first parenthesis: f′(x)=(−18x2)(−9x3)+(−18x2)(−4x2)+(−18x2)(5).Now, distribute −4 and −6x3 across the terms in the second parenthesis: f′(x)=f′(x)+(−4)(−27x2)+(−4)(−8x)+(−6x3)(−27x2)+(−6x3)(−8x).Let's simplify the terms we have so far: f′(x)=162x5+72x4−90x2+108x2+32x−162x5−48x4.Combine like terms to get the final derivative: f′(x)=162x5−162x5+72x4−48x4−90x2+108x2+32x.After combining like terms, we get f′(x)=(−18x2)(−9x3−4x2+5)+(−4−6x3)(−27x2−8x)0.
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