a) (√2+√3)²+(1-√6)² aplicam formula (a+b)²⇒ a²+2ab+b²
si (a-b)² = a²-2ab+b²
(√2)²+2x√2x√3+(√3²) + 1²-2x1x√6+(√6)² = 2+2√6+3+1-2√6+6=9
b) (√6-1)²-(√2-√3)² aplicam formulele si de stiut ca minusul din fata parantezei schimba semnul din paranteza ⇒
(√6)²-2x1x√6+1²-(√2)²+2x√2x√3-(√3)²=6-2√6+1-2+2√6-3=2
c) (√7+3√2)²+(3-√14)² =(√7)² +2x√7x3√2+(3√2)²+3²-2x3x√14+(√14)²=
7+6√14+18+9-6√14+14=7+18+9+14=48
d)(2√3-√5)²-(√15+2)²= (2√3)²-2x2√3x√5+(√5)²-(√15)²-2x√15x2-2²=
12-4√15+5-15-4√15-4= -8√15 -2 aic icred ca e gresala de vreun semn la enunt.
