Odpowiedzi

2009-09-23T20:45:44+02:00
A) (2x - 3)(x+7)=2x²+14x-3x-21=2x²+11x-21
b) (4-5y)(1-6y)=4-24y-5y+30y²=30y²-29y+4
c) -(3+2x)(x-2)=-(3x-6+2x²-4x)=-(2x²-x-6)=-2x²+x+6
d)(3a+5)² = 9a²+30a+25
e)(3a-5)² =9a²-30a+25
f) (a+3)(a-3)=a²-9
2009-09-23T21:36:26+02:00
A) (2x-3)(x+7) = 2x²+14x-3x-21= 2x²+11x-21
b)(4-5y)(1-6y) =4-24y-5y+30y² = 30y²-29y+4
c)-(3+2x)(x-2)= -(3x-6+2x²-4x)=-(2x²-x-6)=-2x²+x+6
d)(3a+5)²= 9a²+30a+25
e)(3a-5)²=9a²-30a+25
f) (a+3)(a-3)=a²-9