maTematika 7

8. b) 8x–3–(5-2x)=4,38x–3–5+2x=4,310x–8=4,310x=12,3x=1,23.9. magaliTis amoxsnamde moswavleebs unda vaCvenoT gansxvaveba orniSna ricxvis Canawersda ab-s Soris. magaliTad, ricxvi 23 niSnavs 2 aTeuls da 3 erTeuls. Canaweri ab ki ada b ricxvebis namravls gvaZlevs. imisaTvis, rom asoebiT CavweroTY ricxvi, romelica aTeulisgan da b erTeulisgan Sedgeba, moswavleebs mivceT Semdegi Canaweri:ab — niSnavs ricxvs, romelic Seicavs a aTeuls da b erTeuls.abc — ricxvi, romlis aseulebis ricxvia a, aTeulebis — b da erTeulebis — c.magram es iqneba aRniSvna, rogor gamoviyenoT es Canaweri gardaqmnebis da gantolebebisamoxsnis SemTxvevaSi. isev davubrundeT ricxviT magaliTs: 23=2·10+3, e.i.a) ab=10a+b; b) abc=100a+10b+c da a.S.;g) a00 b=1000a+b; d) abcd=1000a+100b+10c+d.11. moTxovna gasagebia a) da g) SemTxvevaSi, roca gamosaxuleba Seicavs 4 wevrs,amocana SeiZleba amoixsnas ramdenimenairad:a) x 3 +2x 2 +3x–5= x 3 –(5-2x 2 –3x), an x 3 +2x 2 +3x–5= 2x 2 –(-x 3 –3x+5) da a.S.rogor moviqceT b) SemTxvevaSi?moswavleebi unda mieCvion wevris „gaCenis“ process (gamosaxulebis mniSvnelobaar Seicvleba, Tu mas erTdroulad davumatebT da gamovaklebT erTsa da imavegamosaxulebas). mag.: 4xy–2x 2 =4xy–2x 2 +y 3 –y 3 = y 3 –(-4xy+2x 2 +y 2 ).15. SeadareT:a) 10 7 da 2 8·5 7 . 2 8·5 7 =2·2 7·5 7 =2·(2·5) 7 =2·10 7 ; 10 7