Since the given function is
[tex]f(x)=\int_0^x(t^3+7t^2+4)dt[/tex]
That means
[tex]f^{\prime}(x)=(t^3+7t^2+4)[/tex]
Then to find f''(x) we will differentiate f'(x) with respect to t
[tex]\begin{gathered} f“(x)=3t^{3-1}+7(2)t^{2-1}+0 \\ \\ f“(x)=3t^2+14t \end{gathered}[/tex]
The answer is
[tex]f“(x)=3t^2+14t[/tex]
