If
\[
f(x)=x^3-19x+30
\]
is a real valued function with domain \([-4,1]\), then the value of \(c\) according to Lagrange's Mean Value Theorem for \(f(x)\) is
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For LMVT problems, first compute the average rate of change
\[
\frac{f(b)-f(a)}{b-a},
\]
then equate it to \(f'(c)\). Finally, choose the solution that lies inside the open interval \((a,b)\).