Question

exercitiul 5 ... help plss

Answer 1

1,9 <a<5,7 (1)
2,2<b<4,2 (2)
a. inmultim relatia (1) cu 2 si relatia (2) cu 3 si apoi le adunam
3,8<2a<11,4
6,6<3b<12,6
----------------
10,14<2a+3b<24 |+3,021
13,161<2a+3b+3,021<27,021

b. 1,9·2,2<a·b<5,7·4,2
4,18<a·b<23,94 |-1,523
2,657<a·b-1,523<22,417

c.1,9²<a²<5,7²
3,61<a²<32,49

2,2²<b²<4,2²
4,84<b²<17,64
adunam expresiile obtinute
3,61+4,84<a²+b²<32,49+17,64
8,45<a²+b²<50,13