Odpowiedzi

2009-12-01T16:50:31+01:00
A) 16x²y-12xy dla x=-1/4 ; y=2
16× (-1)² × 2 - 12× (-1)× 2 = 32- (-24) = 32+24= 56

b)6a²(b-2)-4a(b-2) dla a=-1/2;b=1,5
6 × (-1)² × (1,5-2) - 4 × (-1) × (1,5-2) = -6(1,5 - 2) + 4(1,5-2) = -9+12+6-8= 1