1. b3²=6*24=144⇒b3=12
b3=b2*q⇒q=b3/b2=12/6=2
b1=b2/q=6/2=3
2. a1+a2=a1+a1+r= 2a1+r=3
a3+a4=a1+2r+a1+3r= 2a1+5r=12
[tex] \left \{ {{2a1+r=3} \atop {2a1+5r=12}} \right. [/tex]
Daca le scazi obtii 4r=9⇒ r=9/4
2a1+r=3
a1=(3-r)/2=[tex] \frac{3- \frac{9}{4} }{2} = \frac{ \frac{12-9}{4} }{2}= \frac{3}{8} [/tex]
