(a-b)2=a2-2ab+b2
(3-b)2=±
±
b
±
b2
(a-9)2=±
a2±
a
±
(3a-b)2=±
*
2
±
*
*b
±
b2
(a-9b)2=±
a2±
*a*
+
*
2
(3-t)2=±
±
6t±
t2
(3-t)*(3-t)=±
±
6t±
t2
(t-3)*(3-t)=±
t2±
6t±
(2-z)*(2-z)=±
±
z
±
z2
(x-5)*(5-x)=±
x2±
x
±
(2ax-bz)*(2ax-bz)=±
*(
)2
±
*
*bz
±
(bz)2
(vt-5up)*(5up-vt)=±
(vt)2±
*vt*
±
*(
)2
(5-z)*(5-z)=±
±
z
±
z2
(3-x)*(x-3)=±
x2±
x
±
(5x-bz2)*(5x-bz2)=±
*(
)2
±
*
*bz2
±
(bz2)2
(2dp-t)*(t-2dp)=±
t2±
*t*
±
*(
)2