Răspuns:
Explicație pas cu pas:
F
(1/3)²-(441/100-43/10)=1/9-(441-430)/100=1/9-11/100=(100-11·9)/100=
=(100-99)/100=1/100
ex 5
a) (7·5-29)²/100-[(81-77)/20]²=(35-29)²/100-(4/20)²=(6/10)²-(1/5)²=
=(3/5)²-(1/5)²=(3/5+1/5)(3/5-1/5)=4/5·2/5=8/25
b)(7·12)²/10²- (21·3)²/10²=84²/100-63²/100=(84-63)(84+63)/100=
=21·147/100=3·7·3·7²/100=3²·7³/100
c) 3²·7/5-49/4-1/4=9·7/5-50/4=(9·7·4-50·5)/4=(252-250)/4=2/4=1/2
