Question

Descompuneti in factori, grupand convenabil termenii:
1. ax+bx+ax²+bx²
2.x³+x²-4x-4
3.x³+x²-9x-9
4. ax²+x²-9a-9

Answer 1

1. ax+bx+ax²+bx² = x(a+b+ax+bx) = x[(a+b)+ x(a+b)] = x(a+b)(1+x)
2. x³+x²-4x-4 = x²(x+1)-4(x+1) = (x+1)(x²-4) = (x+1)(x+2)(x-2)
3. x³+x²-9x-9 = x²(x+1)- 9(x+1) = (x+1)(x²-9)= (x+1)(x+3)(x-3)
4. ax²+x²-9a-9 = x²(a+1)-9(a+1)= (a+1)(x²-9) = (a+1)(x+3)(x-3)