Răspuns:
(y-4)^3=y³-3*y²*4+3*y*4²-4³=y³-12y²+48y-64
(7x+a)^3 =(7x)³+3*(7x)²*a+3*7x*a²+a³=343x³+147x²a+21xa²+a³
(5a-1)(5a+1) =5a²-1²=25a²-1
(3a+2b)^3=(3a)³+3*(3a)²*2b+3*3a*(2b)²+
(2b)³=27a³+54a²b+36ab²+8b³
FORMULELE:
(a+b)³=a³+3*a²*b+3*a*b²+b³
(a-b)³=a³-3*a²*b+3*a*b²-b³
(a+b)(a-b)=a²-b2
