1.
( 2 * 27^(1/2) + 3^(1/2) )^2 =
( 2 * 27^(1/2) )^2 + 2 * 2 * 27^(1/2) * 3^(1/2) + ( 3^(1/2) )^2 =
4 * 27 + 4 * 81^(1/2) + 3 =
108 + 4 * 9 + 3 =
111 + 36 =
147
2.
19 - 8 * 3^(1/2) =
16 - 2 * 4 * 3^(1/2) + 3 =
4^2 - 2 * 4 * 3^(1/2) + ( 3^(1/2) )^2 =
( 4 - 3^(1/2) )^2