I have stumbled across these 2 problems
$L_1= \{\alpha \mid w \in \{a,b\}^* | \alpha $ has exactly 2 b's$\} $ ,prove that $L =\{ \alpha^n | \alpha ∈ L_1 ,n \ge 0 \}$ is not context free
Given : $P= \{\alpha \mid w \in \{a,b,c\}^* | \alpha $ is palindrom with even length $\} $ and $L_2= \{\beta b^n| b$ ∈ $P^n$ and $n ∈ \mathbb{N} $} prove that $L_2$ is context free.
In both problems we have degree $n$ of a word with length >1,usually in such problems how do we cope with that ?Also any suggestions,tricks or hints how to proceed in these 2 problems or in general with degree $n$ will be very helpful