inegalitatea mediilor

Post on 24-Oct-2015

94 Views

Category:

Documents

16 Downloads

Preview:

Click to see full reader

DESCRIPTION

Matematica

TRANSCRIPT

I. Inegalitatea mediilor

Mh(a1,a2,...,an)¿ n

1a1

+1a2

+…+1an

Mg(a1,a2,...,an)¿ n√a1∗a2∗…∗an

Ma(a1,a2,...,an)¿a1+a2+…+an

n

Mp(a1,a2,...,an)¿ √a12+a2

2+…+ann

n

M h≤M g≤M h≤M p

n

1a1

+ 1a2

+…+ 1an

≤ n√a1∗a2∗…∗an≤a1+a2+…+an

n≤

√a12+a2

2+…+ann

n

II. Inegalitatea lui Bernoulli

(1+x )n≥1+nx , (∀ )n∈N , (∀ ) x≥−1

III. Inegalitatea lui Titu Andreescu

x2

a+ y

2

b=

(x+ y )2

a+b, x , y , a , b>0

Generalizare:x i ,a i>0 i=1 ,n

x1

2

a1

+x2

2

a2

+…+xn

2

an≥(x¿¿1+x2+…+xn)

2

a1+a2+…+an¿

IV. Inegalitatea lui Young

x , y>0α , β>1astfel încâ t1α

+ 1β=1

α+ y

β

β≥xy

V. Inegaliatatea lui Cauchy-Buniakovski-Schwarz(C-B-S)

(a1b1+a2b2)2≤(a¿¿12+a2

2)∗(b12+b2

2 )¿

cu egalitate c ânda1

b1

=a2

b2

Generalizare: (a¿¿1b1+a2b2+…+anbn)

2≤(a¿¿12+a22+…+an

2)∗(b¿¿12+b22+…+bn

2)¿¿¿

cu egalitate c ânda1

b1

=a2

b2

=…=anbn

VI. Inegalitatea lui Minkowski

√(a¿¿1+b1)2+(a2+b2)

2+…+(a¿¿n+bn)2≤√(a1

2+a22+…+an

2)+√(b¿¿12+b22+…+bn

2¿)¿¿¿¿

cu egalitate cânda1

b1

=a2

b2

=…=anbn

top related