Question

1 ) media geometrica (a,b) pentru
a = ( 1 - √2 ) ^2 ( √3 + 1 ) ^2
b = ( 1 + √2 ) ^2 ( √3 - 1 ) ^2

2 ) media aritmetica ponderata a numerelor 50 , 102 cu ponderile 3 si 2

Rog rezolvare detaliata a ambelor exercitii .

Answer 1

a = (1 - √2)² (√3 + 1)²
b = (1 + √2)² (√3 - 1)²
a×b=(1 - √2)² (√3 + 1)²(1 + √2)² (√3 - 1)²=
=[(1 - √2)(1+√2)]²[ (√3 + 1)(√3 - 1)]²=
=(1 - 2)²(3 - 1)²=
=(-1)² ×2²=1×4=4

mg=√a×b=√4=2


2 ) media aritmetica ponderata a numerelor 50 , 102 cu ponderile 3 si 2
(50×3+102×2)/(3+2)=(150+204)/5=354/5=70,8