a,\(A=x^3-2x^2=x^2\left(x-2\right)\)
\(b,\) \(y^2+2y-x^2+1=-x^2-xy-x+xy+y^2+y+x+y+1\)
\(=-x\left(x+y+1\right)+y\left(x+y+1\right)+\left(x+y+1\right)\)
\(=\left(-x+y+1\right)\left(x+y+1\right)\)
\(c,\) \(\left(x+1\right)^2-25=\left(x+1+5\right)\left(x+1-5\right)=\left(x+6\right)\left(x-4\right)\)
a,x3−2x2=x2(x−2)
b,y2+2y-x2+1=(y+1)2-x2=(y+x+1)(y-+x+1)
c, (x+1)2−25=(x+1+5)(x+1−5)=(x+6)(x−4)