If the function $f(x)=x^{3}-6 x^{2}+a x+b$ defined on $[1,3]$ satisfies Roll's theorem for $c=2+\frac{1}{\sqrt{3}}$, then a = ___________, b = __________.
The given function is $f(x)=x^{3}-6 x^{2}+a x+b$.
It is given that $f(x)$ defined on $[1,3]$ satisfies Rolle's theorem for $c=2+\frac{1}{\sqrt{3}}$.
$\therefore f(1)=f(3)$ and $f^{\prime}(c)=0$
Now,
$f(1)=f(3)$
$\Rightarrow 1-6+a+b=27-54+3 a+b$
$\Rightarrow-5+a=-27+3 a$
$\Rightarrow 2 a=22$
$\Rightarrow a=11$
Also,
$f(x)=x^{3}-6 x^{2}+a x+b$
$\Rightarrow f^{\prime}(x)=3 x^{2}-12 x+a$
$\therefore f^{\prime}(c)=0$
$\Rightarrow 3 c^{2}-12 c+a=0$
$\Rightarrow 3 c^{2}-12 c+11=0 \quad(a=11)$
Since both equations $f(1)=f(3)$ and $f^{\prime}(c)=3 c^{2}-12 c+11=0$ are independent of $b$, so $b$ can taken any real value.
$\therefore a=11$ and $b \in \mathrm{R}$
Thus, if the function $f(x)=x^{3}-6 x^{2}+a x+b$ defined on [1, 3] satisfies Roll's theorem for $c=2+\frac{1}{\sqrt{3}}$, then $a=11$ and $b \in \mathrm{R}$.
If the function $f(x)=x^{3}-6 x^{2}+a x+b$ defined on $[1,3]$ satisfies Roll's theorem for $c=2+\frac{1}{\sqrt{3}}$, then a = ___11___, b = ___R___.