Ответ:
Объяснение:1.
A)5a^2-20=5(a^2-4)=5(a-2)(a+2)
B)3x^5-48x=3x(x^+4)(x-2)(x+2)
C)5x^2-20x+20=5(x^2-4x+4)=5(x-2)^2
D)m-n+m^2-n^2=(m+m^2)-(n+n^2)=m(1+m)-n(1+n)=(m-n)(1+m)(1+n)
2.
A)x^3-7x^2=0
x^2(x-7)=0
x1=0
x-7=0
x2=7
B)2x^4-18x^2=0
2x^2(x^2-9)=0
2x^2=0
x^2=0
x1=0
x^2-9=0
(x-3)(x+3)=0
x-3=0 x2=3
x+3=0 x3=-3