Exercise $15$ Comparison of regular expressions

$(4$ points$)$

Show that

$L(a^{**}|b^{**})L((a|b{)}^{**})$

holds. The meaning of the symbol $$ is that

$L(a^{**}|b^{**})subeL((a|b{)}^{**}),$ but not $L(a^{**}|b^{**})=L((a|b{)}^{**})$

$($Note: For the second part you only have to construct a word $w,$ such that $w!$inL$(a^{**}|b^{**})$ and win

$\{$:$L((a|b{)}^{**}).)$