Udowodnij wzór : (a+b)³+a³+3a²b+3ab²+b³ ???

L(lewa strona)=(a+b)(a+b)(a+b)=(a²+ab+ab+b²)(a+b)= (a²+2ab+b²)(a+b)=a³+2a²b+ab²+a²b+2ab²+b³= a³+3a²b+3ab²+b³ = P(prawa strona)

(a-b)³=a³-3a²b+3ab²-b³ (a-b)³=a³-3ab(a-b)-b³ (a+b)³=a³+3a²b+3ab²+b³ (a-b)³ = a³-3ab(a-b)-b³ = a³-3a²b+3ab²-b³