asked 10.0k views
5 votes
Find the derivative of the function using the definition of derivative. f(x) = 4 - 8x + 8x²?

asked
User Axalo
by
8.6k points

1 Answer

4 votes

Final answer:

To find the derivative of the function using the definition of derivative, apply the limit definition of derivative and simplify the expression.

Step-by-step explanation:

To find the derivative of the given function using the definition of derivative, we first need to apply the limit definition of derivative.

The limit definition of derivative states that the derivative of a function f(x) is equal to the limit of the difference quotient as the change in x approaches zero.

Let's apply this definition to the given function:

f(x) = 4 - 8x + 8x²

f'(x) = lim┬(h->0)⁡〖(f(x+h)-f(x))/h〗

Now we can substitute the function into the definition and simplify:

f'(x) = lim┬(h->0)⁡((4-8(x+h)+8(x+h)²)-(4-8x+8x²))/h

f'(x) = lim┬(h->0)⁡(4-8x-8h+8x²+16xh+8h²-4+8x-8x²)/h

f'(x) = lim┬(h->0)⁡(8h+8h²)/h

f'(x) = lim┬(h->0)⁡8+8h = 8

Therefore, the derivative of the function f(x) = 4 - 8x + 8x² using the definition of derivative is 8.

answered
User BJack
by
9.1k points
Welcome to Qamnty — a place to ask, share, and grow together. Join our community and get real answers from real people.