1)3(y-1)²+6y=3(y²-2y+1)+6y=3y²-6y+3+6y=3y²+3
2)8c+4(1-c)²=8c+4(1-2c+c²)=8c+4-8c+4c²=4+4c²
3)4ab+2(a-b)²=4ab+2(a²-2ab+b²)=4ab+2a²-4ab+2b²=2a²+2b²
4)3(x+y)²-6xy=3(x²+2xy+y²)-6xy=3x²+6xy+3y²-6xy=3x²+3y²
5)27.3ˇ4=3ˇ3.3ˇ4=3ˇ7=3.3.3.3.3.3.3=9.9.9.3=729.3=2187
6)(a³.b².c)ˇ4=aˇ12 . bˇ8 .cˇ4