Question

Formule de caclul prescurtat.
Calc:
a) (2+√5)²
b)(√5+√6)²
c)(√6-√2)²
d)(5-√3)²
e)(√5-√3)(√5+√3)
f)(√6-2)(√6+2)

Answer 1

a) (2+√5)²= 2² +  2 ·2·√5 +√5² = 4+ 4√5+5 = 9 +4√5
b)(√5+√6)²=√5² +2·√5·√6+√6²=5+ 2√30+6 =11+2√30
c)(√6-√2)²=√6²-2·√6·√2+ √2²= 6-2√12+2= 8-2·2√3= 8- 4√3= 4(2-√3)
d)(5-√3)²= 5²-2·5·√3+√3²=25-10√3+3=28-10√3=2(14-5√3)
e)(√5-√3)(√5+√3)= √5²-√3²=5-3=2
f)(√6-2)(√6+2) =√6²-2²= 6-4=2
Sper ca te-am ajutat !