a) (x-2)²+(2x-3)²=x²-4x+4+(4x²-12x+9)=x²-4x+4+4x²-12x+9=
5x²-16x+13
b) (3y-1)²-(2y-5)(2y+5)-3y²=9y²-6y+1-(4y²-25)=9y²-6y+1-4y²+25=5
y²-6y+26
c) (5a-2)(5a+2)-(3a-1)²+4a²=25a²-4-(9a²-6a+1)+4a²=25a²-4-9a²+6a-1=16a²+6a-5
d) (4b+3)²-2(b-3)(b+3)-(b-1)²=16b²+24b+9-2(b²-9)-(b²-2b+1)=
16b²+24b+9-2b²+18-b²+2b-1=13b²+26b+26
e) 5(x+2)²-3(x-3)²-(x+5)(x-5)= 5(x²+4x+4)-3(x²-6x+9)-(x²-25)=
5x²+20x+20-3x²+18x-27-x²+25=x²+38x+28
