[tex]\displaystyle\bf\\\textbf{Din text stim ca:}\\\\AB~||~A_1B_1~||~A_2B_2||~A_3B_3\\\\\textbf{Din desen observam:}\\\\Segmentele~~AA_1,~A_1A_2,~A_2A_3~~\textbf{sunt taiate de o liniuta mica.}\\\\\implies~ AA_1=A_1A_2=A_2A_3\\\\Segmentele~~BB_1,~B_1B_2,~B_2B_3~~\textbf{sunt taiate de 2 liniute mici.}\\\\\implies~ BB_1=B_1B_2=B_2B_3\\\\\\Din~~AA_1=A_1A_2=A_2A_3~~~si~~~BB_1=B_1B_2=B_2B_3~~~~rezulta~ca:\\\\AB,~A_1B_1,~A_2B_2,~A_3B_3~~~sunt~paralele~echidistante.[/tex]
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[tex]\displaystyle\bf\\\textbf{Secanta AA3 este inclinata spre dreapta si }\\\textbf{Secanta BB3 este inclinata spre stanga astfel incat:}\\AB<A_1B_1<A_2B_2<A_3B_3\\\\\textbf{Deoarece secantele }AA_3~si~BB_3~sunt~repte~(nu~sunt~parabole,~etc)\\\\Rezulta~ca~ segmentele~~AB,~A_1B_1,~A_2B_2,~A_3B_3\\\\sunt~liniar~crescatoare~ca~elementele~unei~progresii~aritmetice.\\\\Calcule:\\AB=8~cm\\A_1B_1=11~cm\\Ratia~~r=11-8=3\\\\A_2B_2=A_1B_1+r=11+3=14~cm\\\\A_3B_3=A_2B_2+r=14+3=17~cm[/tex]
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[tex]\displaystyle\bf\\Raspuns:\\\\\boxed{\bf~A_2B_2=14~cm}\\\\\boxed{\bf~A_3B_3=17~cm}[/tex]
