ПОЖАЛУЙСТА. УМОЛЯЮ.

1.a) $a^{2} - 6ab +9 b^{2} = (1a-3b)^{2}$
b) $9a^{2} +6ab + b^{2} = (3a+b)^{2}$

2.a) $\frac{4}{9} a^{2} -2ab + \frac{9}{4} b^{2} = (\frac{2}{3}a )^{2} -2ab \frac{2}{3} *\frac{3}{2} + (\frac{3}{2}b)^{2} = (\frac{2}{3}a - \frac{3}{2}b)^{2}$
b) $\frac{1}{4} a^{2} -ab + b^{2} = ( \frac{1}{2}a )^{2} -2* \frac{1}{2}ab + b^{2} = ( \frac{1}{2}a -b)^{2}$

3. a) $1 - 2ab + a^{2} b^{2} = (1-ab)^{2}$
b) $a^{4} +2 a^{2} b + b^{2} = ( a^{2} )^{2} + 2 a^{2}b + b^{2} = (a^{2} +b)^{2}$