👤

2. Calculați, folosind formulele de calcul prescurtat:a) (2√3+3)(2√3-3)-(√2-1)(√2+1); b) (3-√6)(3+√6) + (√3-1)(√3+1)-(3-√5)(3+√5); c) (4-2√5)(4+2√5)+(3√2-5) (3√2+5)-(√6 + √2)(√6-√₂); d) (3√3-5) (3√3+5)-(2√2-1)(2√2+1); e) (√5-2)(√5 +2)-(3-4) (3√2+4).​