29. Calculaţi:
a)
(√2-1)(√2+1)+(√2+1);
b) (3√2-√6) (3√2+√6)-(√3+√2)² + √24;
c) (√5+1)²-(√5-1)²-√5 (√5-1)(√5+1);
d) (3√2-2√3)(√12+√18)-(2-√3)²-√√48.