e/=\(2x^2-2x+5x-5=2x\left(x-1\right)-5\left(x-1\right)\)
=\(\left(2x-5\right)\left(x-1\right)\)
f/=\(x^2-4xy+4y^2-3xy+6y^2\)
=\(\left(x-2y\right)^2-3y\left(x-2y\right)\)=\(\left(x-2y\right)\left(x-2y-3y\right)\)
=\(\left(x-2y\right)\left(x-5y\right)\)
a/ = \(\left(2x-5\right)\left(2x+5\right)+\left(2x+7\right)\left(5-2x\right)\)
=\(\left(2x-5\right)\left(2x+5-2x-7\right)\)=\(\left(2x+5\right)\left(-2\right)\)
b/=\(\left(x+2\right)^2-y^2\)=\(\left(x+2+y\right)\left(x+2-y\right)\)
c/=\(\left(x-1\right)^3\)
d/=\(x^2-5x+3x-15=x\left(x-5\right)-3\left(x-5\right)\)
=\(\left(x-5\right)\left(x-3\right)\)
a, (2x-5)(2x+5)+(2x+7))(5-2x)
=(2x-5)(2x+5)-(2x+7)(2x-5)
=(2x-5)(2x+5-2x-7)
=-2(2x-5)
b,x2+4x-y2+4
=(x2+4x+4)-y2
=(x+2)2-y2
=(x+2-y)(x+2+y)
