Product Rule Derivative Problem

In summary, the conversation was about using the product rule to differentiate a function and the mistake made in simplifying the first term. The textbook provided the correct answer as (1 - 5t2)/(2√t).
  • #1
Burjam
52
1

Homework Statement



Use the product rule to differentiate the function:

h(t) = √t(1-t2)

Homework Equations



d/dx[f(x)g(x)] = f(x)g'(x) + g(x)f'(x)

The Attempt at a Solution



(see attachment image)

I checked the back of the textbook and my solution was wrong. The textbook says the answer is (1 - 5t2)/(2√t). What did I do wrong? How do you get this answer?
 

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  • #2
Between lines 3 and 4 of your work you incorrectly simplified the first term like this:
[tex]t^{\frac{1}{2}}(-2t)=-2\sqrt t[/tex]Otherwise, I agree with your work.
 
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  • #3
Ahh good catch. You would then just do (-2t√t)(2√t) and get -4t2. Add that to 1 - t2 on the numerator and you get (1 - 5t2) / 2√t, the correct answer in the textbook. Thanks.
 

FAQ: Product Rule Derivative Problem

What is the product rule in calculus?

The product rule is a rule in calculus that is used to find the derivative of a function that is the product of two other functions. It states that the derivative of a product of two functions f(x) and g(x) is equal to the first function f(x) multiplied by the derivative of the second function g(x), plus the second function g(x) multiplied by the derivative of the first function f(x).

2. How do you apply the product rule to find the derivative of a function?

To apply the product rule, you first identify the two functions that are being multiplied together in the original function. Then, you take the derivative of the first function and multiply it by the second function. Next, you take the derivative of the second function and multiply it by the first function. Finally, you add these two products together to get the derivative of the original function.

3. Can the product rule be applied to more than two functions?

Yes, the product rule can be applied to any number of functions that are multiplied together. You simply take the derivative of each individual function and multiply them together, then add all of these products together to get the overall derivative of the original function.

4. What is the purpose of the product rule in calculus?

The product rule is an important tool in calculus that allows us to find the derivative of functions that are the product of multiple other functions. This is useful in many applications, such as finding the rate of change of a quantity that is affected by multiple variables, or in optimizing functions that involve products of other functions.

5. Are there any alternative methods for finding the derivative of a product of functions?

Yes, there are other methods for finding the derivative of a product of functions, such as the quotient rule and the chain rule. However, the product rule is often the simplest and most straightforward method to use, and it can be applied to any number of functions. It is a fundamental concept in calculus that is essential for solving many types of problems.

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