Question

Упростить выражение ​

Answer 1

$\displaystyle\bf\\2)\\\\(b+2)(b^{2} -2b+4)-b(b^{2} -1)=b^{3} +2^{3} -b\cdot b^{2} -b\cdot (-1)=\\\\=b^{3} +8-b^{3} +b=b+8\\\\\\4)\\\\y^{3} -(y-3)(y^{2}+3y+9)=y^{3} -(y^{3} -3^{3} )=y^{3} -y^{3} +27=27$