Zapisz w jak najprostszej postaci: a) (a-3)(2a-5)-(3a+1)² b) (3a-2b)²+(a-2b)(a+2b)-3a(2a-b)
stefanie15
A) (a-3)(2a-5)-(3a+1)²=(2a²-5a-6a+15)-(9a²+6a+1)=2a²-5a-6a+15-9a²-6a-1=-7a²-5a+14 b) (3a-2b)²+(a-2b)(a+2b)-3a(2a-b)=(9a²-6ab+4b²)+(a²-4b²)-(6a²-3ab)=9a²-6ab+4b²+a²-4b²-6a²+3ab=4a²-3ab
b) (3a-2b)²+(a-2b)(a+2b)-3a(2a-b)=(9a²-6ab+4b²)+(a²-4b²)-(6a²-3ab)=9a²-6ab+4b²+a²-4b²-6a²+3ab=4a²-3ab