f(x)=(x2+1)x2−ax+2+cos∣x∣ Notice that cos(−x)=cosx=cos∣x∣ which means cos∣x∣ is differentiable everywhere in x∈R $\begin{aligned}
& \Rightarrow f(x) \text { can be non differentiable where }\left|x^2-a x+2\right| \
& =0
\end{aligned}\Rightarrow x^2-a x+2=0$
⇒4−2a+2=0⇒a=3 ⇒(x2−3x+2)=0⇒x=1,2 β=1 distance of (α,β) from line $\begin{aligned}
& 12 x+5 y+10=0 \
& \Rightarrow \frac{|2(12)+5(1)+10|}{13}=\frac{39}{13}=3
\end{aligned}$