Zapisz w jak najprostszej postaci: (x+1)(x-2)+(x+2)(x-1) b)(5k+n)(k-2n)-k(4k+n) c)(4y+3)(y-2)-2y(4-2y) d)2a(3a<2potegi>-(a<2potega>+2)(a+2)

(x+1)*(x-2)+(x+2)*(x-1)=x²-2x+x-2+x²-x+2x-2=2x²-4 b)=5k²-10kn+kn-2n²-4k²-kn=k²-10kn c)=4y²-8y+3y-6-8y+4y²=8y²-13y-6 d)2a(3a²-(a²+2)*(a+2)=2a(3a²-(a³+2a²+2a+4)=2a(3a²-a³-2a²-2a-4)=6a³-2a⁴-4a³-4a²-8a=2a³-2a⁴-4a²-8a