The Student Room Group

C1: Quick maths question

Can someone explain to me why we can differentiate and complete the square to find the minimum and maximum points?
You can differentiate and find the places where the differential is equal to 0, as these are the places where the curve is stationary.

You can only complete the square for quadratics. This approach finds the point on the curve that is midway between the roots, which also gives the maxima/minima.
Original post by morgan8002
You can differentiate and find the places where the differential is equal to 0, as these are the places where the curve is stationary.

You can only complete the square for quadratics. This approach finds the point on the curve that is midway between the roots, which also gives the maxima/minima.


Ah that makes sense, thank you!

What's the difference between the minimum/maximum and the maxima/minima?
Original post by creativebuzz
Ah that makes sense, thank you!

What's the difference between the minimum/maximum and the maxima/minima?

No difference, just flows a little better.
Original post by creativebuzz
Ah that makes sense, thank you!

What's the difference between the minimum/maximum and the maxima/minima?


minimum/maximum - singular
maxima/minima - plural (e.g. cubics etc)

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