Question 311854
f (x) = - x^2 + 2x - 1
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}
X=(-2+-SQRT[2^2-4*-1*-1])/2*-1
X=(-2+-SQRT[4-4])/-2
X=(-2+-SQRT0)/-2
X=-2/-2=1 ANS.
F(2)=-2^2+2*2-1
F(2)=4+4-1
F(2)=7 ANS
F(7)=-7^2+2*7-1
F(7)=-49+14-1
F(7)=-50+14
F(7)=-36 ANS.
{{{ graph( 300, 200, -6, 5, -10, 10,  -x^2 +2x -1) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, -x^2 +2x -1).