a.
\(\left(3x+1\right)^2-\left(x+1\right)^2\\ =2x\left(4x+2\right)\)
b.https://hoc24.vn/hoi-dap/question/531769.html
Mình làm bài này r ; mà nó dài nên k mún làm lại
c.
\(5x^2-10xy+5y^2-20z^2\\ =5\left(x^2-2xy+y^2-4z^2\right)\\ =5\left(\left(x-y\right)^2-4z^2\right)\\ =5\left(x-y-2z\right)\left(x-y+2z\right)\)
m)
\(x^4+4\\ =\left(x^4+4x^2+4\right)-4x^2\\ =\left(x^2+2\right)^2-4x^2\\ =\left(x^2+2-2x\right)\left(x^2+2+2x\right)\)
A) (3x+1)2-(x+1)2
=9x2+6x+1-x2-2x-1
=8x2+4x
= 4x(2x+1)
C) 5x^2-10xy+5y^20z^2
=5x(x-2y)+5(y^2-4z^2)
=5(x[x-2y]+[y^2-4z^2])
M) x^4 +4
=(X^2+2)^2
d) 16x-5x\(^2\)-3
= -5x\(^2\)+15x+x-3
= -5(x-3)+(x-3)
=(-5+1)(x-3)
n) \(x^3-2x^2+x-xy^2\)
= x[(x\(^2\)-2x+1-y\(^2\))]
= x[(x-1)\(^2\)-y\(^2\)]
= x(x-1-y)(x-1+y)
