Current location - Training Enrollment Network - Mathematics courses - 20 13 national college entrance examination volume 1 science mathematics question 5
20 13 national college entrance examination volume 1 science mathematics question 5
It seems that what you are wondering is the maximum value, so I'll start directly from here.

S = 4t-t 2 This is a quadratic function. Let's look at its symmetry axis first, and the symmetry axis is x=2, because the image of the function is downward, and there is a maximum at this time.

And 2 is in the set t, so the maximum value of the quadratic function is: 4 times 2-2 squared =4.

Answer a.