x2-2xy+y2-z2+2zt-t2
=(x2-2xy+y2)-(z2-2zt+t2)
=(x-y)2-(z-t)2
=(x-y+z-t)(x-y-z+t)
x2 – 2xy + y2 – z2 + 2zt – t2 = (x2 – 2xy + y2) – (z2 – 2zt + t2)
= (x – y)2 – (z – t)2
= [(x – y) – (z – t)] . [(x – y) + (z – t)]
= (x – y – z + t)(x – y + z – t)
\(x^2-2xy+y^2-z^2+2zt-t^2\)
= \(\left(x^2-2xy+y^2\right)-\left(z^2-2zt+t^2\right)\)
= \(\left(x-y\right)^2-\left(z-t\right)^2\)
=\(\left[\left(x-y\right)+\left(z-t\right)\right]\left[\left(x-y\right)-\left(z-t\right)\right]\)
= \(\left(x-y+z-t\right)\left(x-y-z+t\right)\)
Trần Gia Huy
x2 – 2xy + y2 – z2 + 2zt – t2 = (x2 – 2xy + y2) – (z2 – 2zt + t2)
= (x – y)2 – (z – t)2
= [(x – y) – (z – t)] . [(x – y) + (z – t)]
= (x – y – z + t)(x – y + z – t)
Ai k mình và kết bạn với mình mình sẽ trả ơn .