a. find the derivative of f at x. that is, fi...
a. find the derivative of f at x. that is, find f(x). b. find the slope of the tangent line to the graph of f at each of the two values of x given to the right of the function. f(x)=3.9x² + 5.7x, x = - 1, x = 4 a. f(x)=7.8x + 5.7 (simplify your answer. use integers or decimals for any numbers in the expression.) b. at x = - 1, the slope of the tangent line to the graph of f is . (type an integer or a decimal.)
Answer
# Explanation:
## Step1: Substitute x = -1 into f'(x)
We know f'(x)=7.8x + 5.7, substituting x=-1 gives f'(-1)=7.8×(-1)+5.7.
## Step2: Calculate the value
f'(-1)=-7.8 + 5.7=-2.1
# Answer:
-2.1