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For f(x) = √(3x + 28), find f'(x) using the definition of the derivative.

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Final answer:

To find the derivative of f(x) = √(3x + 28) using the definition of the derivative, we need to use the limit definition of the derivative. The derivative is the limit of the difference quotient as h approaches 0, where the difference quotient is (f(x + h) - f(x)) / h. By simplifying the difference quotient and taking the limit, we find that the derivative of f(x) = √(3x + 28) is f'(x) = 3 / (2√(3x + 28)).

Step-by-step explanation:

To find the derivative of f(x) = √(3x + 28) using the definition of the derivative, we need to use the limit definition of the derivative. The derivative is the limit of the difference quotient as h approaches 0, where the difference quotient is (f(x + h) - f(x)) / h.

So, let's start by evaluating the difference quotient:

(f(x + h) - f(x)) / h = (√(3(x + h) + 28) - √(3x + 28)) / h

Next, we need to simplify this expression. We can use the difference of squares formula to simplify the numerator:

(√(3(x + h) + 28) - √(3x + 28)) / h = ((3(x + h) + 28) - (3x + 28)) / (h(√(3(x + h) + 28) + √(3x + 28))))

Finally, we can simplify further and cancel out the common terms:

((3(x + h) + 28) - (3x + 28)) / (h(√(3(x + h) + 28) + √(3x + 28)))) = 3 / (√(3(x + h) + 28) + √(3x + 28)))

Now, take the limit as h approaches 0:

lim(h → 0) 3 / (√(3(x + h) + 28) + √(3x + 28))) = 3 / (2√(3x + 28))

Therefore, the derivative of f(x) = √(3x + 28) is f'(x) = 3 / (2√(3x + 28)).

User Alexey Muravyov
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