[질문] *특 (a+b+c)(a²+b²+c²-ab-bc-ca) 를곱셈공식같은걸이용해서쉽게전개하는법이잇나요

ab(a+b)+bc(b+c)+ca(c+a)+2abc =a제곱b+ab제곱+b제곱c+bc제곱+c제곱a+ca제곱+2abc =(b+c)a제곱+(b제곱+c제곱+2bc)a+bc(b+c)