1.
(2xy+3a)2
=(2xy+3a)(2xy+3a)
=(2xy)(2xy)+(2xy)(3a)+(3a)(2xy)+(3a)(3a)
=4x2y2+6axy+6axy+9a2
=4x2y2+12axy+9a2
2.
(5t2−8)(2)
=(5t2+−8)(2)
=(5t2)(2)+(−8)(2)
=10t2−16
3.
=9m2n3−16n
4.
x=5+√26 or x=5−√26
4.2
x^2+1\ \frac{2}{x^2}=
