[tex]y=(x-1)^2 +1 \\ \\ For \ the \ quadratic \ function \\ \\ f(x) =a(x-h)^2+k \\ \\ where \ a, \ h \ and \ k \ are \ real \ numbers \ with \ a \neq 0 , \\ \\ the \ vertex \ is \ (h,k) =(1,1) \\ \\ a \ symmetry \ about \ the \ vertical \ line \ x = h \\ \\ x= 1[/tex]