Final answer:
To find function f(x), integrate the derivative f′(x)=8x^3 1/x, simplify, and use the initial condition f(1)=-3 to determine the constant of integration. The resulting function is f(x)=8/5 x^5 - 31/5.
Step-by-step explanation:
To find the function f(x) from the derivative f'(x) = 8x31/x, for x > 0, with the condition f(1) = -3, we need to integrate the given derivative.
Step 1: Integrate the derivative f'(x) to get f(x).
F(x)dx = ∫ 8x31/x dx
Step 2: Simplify and integrate the function.
F(x) = ∫ 8x4 dx
Step 3: Find the antiderivative.
F(x) = 8/5 x5 + C, where C is the integration constant.
Step 4: Use the initial condition f(1) = -3 to solve for C.
8/5(1)5 + C = -3 → C = -3 - 8/5
Step 5: Write the final function f(x).
f(x) = 8/5 x5 - 31/5
This function satisfies both the derivative and the initial condition given.