Résoudre une de ces équations svp Merci!

a) f(x)=1/3(x-3)²
=1/3(x²-6x+9)
=1/3x²-2x+3

b) f(x)=3/1000(x-20)²+25
=3/1000(x²-40x+400)+25
=3/1000x²-6/50x+1,2+25
=0,003x²-0,12x+26,2

c) f(x)=-2(x-5)²-2
=-2(x²-10x+25)-2
=-2x²+20x-52