Zapisz w jak najprostszej postaci: a)abc-(abc-(-xyz-(xyz-abc))) b)s²t-(st²-(s²t-(st²-s²t))) c)x²yz-(xy²z-(xyz²-(x²yz-xy²z))) Proszę o pomoc w tym zadaniu

a)abc-(abc-(-xyz-(xyz-abc))) = = abc-(abc-(-xyz -xyz+abc))= =abc-(abc +xyz +xyz-abc) = = abc-abc -xyz -xyz +abc= -2xyz + abc b)s²t-(st²-(s²t-(st²-s²t))) = = s²t-(st²-(s²t-st²+s²t)) = = s²t-(st²-s²t +st²-s²t) = = s²t-st² +s²t -st²+s²t = = 3s²t - 2st² c) x²yz-(xy²z-(xyz²-(x²yz-xy²z)))= = x²yz-(xy²z-(xyz²-x²yz+xy²z))= = x²yz-(xy²z-xyz²+x²yz-xy²z)= = x²yz-xy²z +xyz²-x²yz+xy²z= = xyz²