(a-b)²=a²-2ab+b²
1) (m-1/2)²=m²-2m(1/2)+(1/2)²=m²-m+(1/4)
2) (a-1/5)²=a²-2a(1/5)+(1/5)²=a²-2a/5+(1/25)
3)(x/2-y/3)²=(x/2)²-2(x/2)(y/3)+(y/3)²=(x²/4)-(xy/3)+(y²/9)
4) (a/4-b/3)²=(a/4)²-2(a/4)(b/3)+(b/3)²=a²/16-ab/6+(b²/9)
5) [(2 +1/3)-(1+1/2)b]²=(7/3-(3/2)b)²=(7/3)²-2(7/3)(3/2)b+((3/2)b)²=
=49/9-7b+(9/2)b²
6) [(1 +2/3)m-(1+2/5)n]²=((5/3)m-(7/5)n)²=((5/3)m)²-2(5/3)m(7/5)n+((7/5)n)²=
=(25/9)m²-(14/3)mn+(49/25)n²