Question

Daca 1 < a < 4 si 3 < b < 5, atunci, varianta corecta este........
a) 1 < ab < 5 b) 3 < ab < 20
c) 2 > ab > -20 d) 1 < ab < 16

Answer 1

$1\ \textless \ a\ \textless \ 4 \\ 3\ \textless \ b\ \textless \ 5$
$1*3\ \textless \ a*b\ \textless \ 4*5$ ⇒ $3\ \textless \ ab\ \textless \ 20(b)$

Answer 2

a ={2,3} b={4} atunci varianta: a) 1<24<5. Fals. b)3<24<20. Fals. c)2>24>-20. Fals. d)1<24<16. Fals. !!!!!!!! ACEST EXERCITIU ESTE ERONAT !!!!!!!