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Răspunsuri la întrebare
Răspuns:
Explicație pas cu pas:
a) -1/2+3/4=-2/4+3/4=1/4
b) -5/6-(-1/6)=-5/6+1/6=-4/6=-2/3
c) (-7/15)·(+5/7)=(-7)·(+5)/15·7=-5/15=-3
d) (-9/8):(-3/4)=(-9/8)·(-4/3)=(-9)·(-4)/8·3=9/2·3=3/2
e) (-1/2)³=-1/8
f) (-2 2/3)⁻²= (-8/3)⁻²=1/(-8/3)²=(3/-8)²=9/64
g) -3/8·(-3/8-3/8·5/3)= -3/8·( -3/8-3·5/8·3)= -3/8·( -3/8-5/3)=
3/8·( 3/8+5/3)=3/8·(3·3+5·8)/24=3/8·49/24=3·49/8·24=49/8·8=49/64
h) [0,05+18/19·(5/12-11/30-7/45)]:0,025=[5/100+18/19·(5·15-66-28)/180]:25/1000= [5/100+18/19·(75-66-28)/180]:1/40= [5/100+18/19·(-19/180)]:1/40=[5/100-(18·19)/(19·180]:1/40=
(5/100-18/180):1/40=(5/100-1/10):1/40=
(5-10)/100:1/40=-5/100·40/1=-200/100=-2
[5/100+18/19(12·15-11·6-7·4)]:25/1000=[5/100+18/19(180-66-28)/180]:25/1000=[5/100+18/19·86/180]:25/1000= [5/100+(18/19)·18·86/19·180]:25/1000=
[5/100+(18/19)·86/190]:1/40