Video Transcript
Given that π of π₯ is a quadratic function and π₯ equals four is a root of the equation π of π₯ equals zero, what is the value of π of four?
Weβre told that π₯ equals four is a root of the equation. Roots of a function are the π₯ intercepts. And the π¦-coordinate of points lying on the π₯-axis is zero. So the place of the roots are where π of π₯ equals zero.
The function of π₯ equal to zero, π of four in this case, is equal to zero. Because π₯ equals four is a root of this equation, if we plug in four for π₯, the outcome is going to be zero. The function of four equals zero.