Part of the graph $f(x)=a x^3+b x^2+c x+d$ is shown in the figure Then $b$ is equal to

Question

Professor PC Thomas Classes · Answer

A zero-centered symmetric parabola establishes $f(x) = bx^2 + d$. Y-intercept yields $d=2$. X-intercept at $x=1$ dictates $b+2=0 \Rightarrow b=-2$.