{"id":5674,"date":"2021-09-27T19:47:38","date_gmt":"2021-09-27T14:17:38","guid":{"rendered":"https:\/\/mathemerize.com\/?p=5674"},"modified":"2021-11-13T16:55:49","modified_gmt":"2021-11-13T11:25:49","slug":"what-is-the-point-of-inflection","status":"publish","type":"post","link":"https:\/\/mathemerize.com\/what-is-the-point-of-inflection\/","title":{"rendered":"What is the Point of Inflection ?"},"content":{"rendered":"
Here you will learn what is the point of inflection and properties of maxima and minima.<\/p>\n
Let’s begin –<\/p>\n
A point of inflection is a point at which a curve is changing concave upward to concave downward, or vice versa.<\/p>\n
<\/p>\n
\nA curve y = f(x) has one of its points x = c as an inflection point, if<\/p>\n
(i) f”(c) = 0 or is not defined and<\/p>\n
(ii) f”(x) changes sign as x increases through x = c.<\/p>\n
The later conditions may be replaced by f”'(c) \\(\\ne\\) 0 when f”'(c) exists.<\/p>\n
Thus, x = c is a point of inflection if f”(c) = 0 and f”'(c) \\(\\ne\\) 0.<\/p>\n<\/blockquote>\n
Example<\/span><\/strong> : The point of inflection for the curve f(x) =\\(x^{5\/3}\\) is –<\/p>\n
(A) (1, 1) <\/p>\n
(B) (0, 0)<\/p>\n
Solution<\/span><\/strong> : Here, f”(x) = \\(10\\over 9x^{1\/3}\\)<\/p>\n
from the given points we find that (0, 0) is the point of the curve where<\/p>\n
f”(x) does not exist but sign of f”(x) changes about this point.<\/p>\n
Hence (0, 0) is the required point.<\/p>\n
Properties of Maxima and Minima <\/h2>\n
(i) If f(x) is continous function in its domain, then atleast one maximum or one minimum must lie between two equal values of f(x).<\/p>\n
(ii) Maxima and minima occur alternately, that is, between two maxima there is one minimum and vice-versa.<\/p>\n
(iii) If f(x) \\(\\rightarrow\\) \\(\\infty\\) as x \\(\\rightarrow\\) a or b and f'(x) = 0 only for one value of x (say c) between a and b, then f(c) is necessarily the minimum and the least value.<\/p>\n
If f(x) \\(\\rightarrow\\) -\\(\\infty\\) as x \\(\\rightarrow\\) a or b, then f(c) is necessarily the maximum and the greatest value.<\/p>\n
\nRelated Questions<\/h3>\n
Find the point of inflection for the curve y = \\(x^3 \u2013 6x^2 + 12x + 5\\).<\/a><\/p>\n
Find the inflexion point of f(x) = \\(3x^4 \u2013 4x^3\\).<\/a><\/p>\n