svp aidé moi faire mon DM je dois le rendre pour demain

1/5-3/4+1/2=4/20-15/20+10/20
=-1/20
13-7/3=39/3-7/3=32/3
(1/4-1/3)+(-2)=(3/12-4/12)-2
=-1/12-2=-1/12-24/12=-25/12
5/4×4/9×18/35=5×1/9×18/35
=5×1×2/35=10/35=2/7
3/4×(-4/9)=3×(-1/9)=-1/3
(-3/4)^3=-3/4×(-3/4)×(-3/4)
=-9/12=-3/4