question archive Quadratic functions have graphs called parabolas
Subject:MathPrice: Bought3
Quadratic functions have graphs called parabolas.
The first graph of y = x2x2 has both "ends" of the graph pointing upward. You would describe this as heading toward infinity. The lead coefficient (multiplier on the x2x2) is a positive number, which causes the parabola to open upward.
Compare this behavior to that of the second graph, f(x) = −x2-x2. Both ends of this function point downward to negative infinity. The lead coefficient is negative this time.
Now, whenever you see a quadratic function with lead coefficient positive, you can predict its end behavior as both ends up. You can write: as x→∞,y→∞x→∞,y→∞ to describe the right end, and as x→−∞,y→∞x→-∞,y→∞ to describe the left end.
Last example:
Its end behavior: as x→∞,y→−∞x→∞,y→-∞ and as x→−∞,y→−∞x→-∞,y→-∞ (right end down, left end down)