[질문] (x+1)(x+3)(x+5) 풀어주세요ㅠㅠ

(x+1)(x+3)(x+5)를 전개하면, (x+1)(x+3)(x+5)=(x*x+3*x+1*x+1*3)(x+5)=(x^2+4x+3)(x+5)=(x^2*x+4x*x+3*x+5*x^2+5*4x+3*5) = x^3+9x^2+23x+15가 됩니다.