1. Aufgabe:
(x+2)*(4+b)-(a-1)*(y+3)-(b-2)*(1-x)+y*(a-1)-2bx-13
=4x +xb +8 +2b -(ay +3a -y-3) -(b-bx-2+2x) +ya -y -2bx -13
=4x +xb +8 +2b -ay -3a +y+3 -b+bx+2-2x +ya -y -2bx -13
=4x +2b -ay -3a -b-2x +ya
=2x +b -3a
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2.Aufgabe:
[a*(x-y)-b*(y-x)]*4c-x[(y+3c)*a+3bc]+y*[(2c+x)*a+4bc]
=[ax -ay -by+bx] *4c -x[ya +3ca+3bc] +y*[(2c+x)*a+4bc]
=4acx -4acy -4bcy +4bcx -axy -3cax -3bcx +2acy +axy +4bcy
=acx -2acy +bcx
=c(ax -2ay+bx)