a)
\(=x^2-6x-x+6=x\left(x-6\right)-\left(x-6\right)=\left(x-1\right)\left(x-6\right)\)
b)
\(=x^2+5x+7x+35=x\left(x+5\right)+7\left(x+5\right)=\left(x+5\right)\left(x+7\right)\)
c)
\(=x^2-8x+7x-56=x\left(x-8\right)+7\left(x-8\right)=\left(x-8\right)\left(x+7\right)\)
d)
\(=5x^2-5x+4x-4=5x\left(x-1\right)+4\left(x-1\right)=\left(x-1\right)\left(5x+4\right)\)
e)
\(=\left(x^2\right)^2+16x^2+8^2-16x^2=\left(x^2+8\right)^2-16x^2=\left(x^2+8-4x\right)\left(x^2+8+4x\right)\)
g)
\(=\left(2x^2\right)^2+4x^2+1-4x^2=\left(2x^2+1\right)^2-4x^2=\left(2x^2+1-2x\right)\left(2x^2+1+2x\right)\)
h)
\(=\left(2x^2\right)^2+36x^2+9^2-36x^2=\left(2x^2+9\right)^2-36x^2=\left(2x^2+9-4x\right)\left(2x^2+9+4x\right)\)
i)
\(=\left(8x^2\right)^2+16x^2y^2+\left(y^2\right)^2-16x^2y^2=\left(8x^2+y^2\right)^2-16x^2y^2=\left(8x^2+y^2-4xy\right)\left(8x^2+y^2+4xy\right)\)
