Question

If the graph of quadratic polynomial ax² + bx + c cuts negative direction of y-axis, then what is the sign of c?

Answer 1

Since graph of quadratic polynomial `f(x) = ax^2 + bx + c` cuts negative direction of y-axis

So put x = 0 to find the intersection point on y-axis

` y = 0 + 0 + c +c `

So the point is `(0, c)`

Now it is given that the quadratic polynomial cuts negative direction of y

So `c < 0`