1) S=a²
S=4²=16
2) S=ab/2
S=3×6/2=9
3) S=ah
S=6×3=18
4) S= ab
S=3×7=21
5) S=ah/2
S=8×3/2=12
6) S=ah/2
S=3×7/2=10,5
Shdhdffhv fdrfbgrgjgf gchchfhff gcjvjgebk???
Х^2(Х-у)+х(Х-у)=(Х-у)(х^2+Х)
S=(404+414+...494)+(440+441+...449)+(144+244+...944)=
=(100*4*9+10(0+1+...9)+1*4*9)+
+(100*4*9+10*4*9+1(0+1+...9))+
+(100(1+...9)+10*4*9+1*4*8)=
=(3600+450+36)+(3600+360+45)+(4500+360+32)=
=12983