These points may be called turning points of the given
function Further, observe that at turning points, the graph has either a little hill or a little
valley Roughly speaking, the function has minimum value in some neighbourhood
(interval) of each of the points A and C which are at the bottom of their respective
Rationalised 2023-24
APPLICATION OF DERIVATIVES
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valleys Similarly, the function has maximum value in some neighbourhood of points B
and D which are at the top of their respective hills