Positive part of sine function: Difference between revisions

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(Created page with "{{particular function}} ==Definition== This function of one variable, denoted <math>\sin^+</math> is defined as the [[defining ingredient::composite of two functions|compos...")
 
 
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The function also has the following description using a [[piecewise definition of function|piecewise definition]]:
The function also has the following description using a [[piecewise definition of function|piecewise definition]]:


<math>x \mapsto \left\lbrace \begin{array}{rl} \sin x, & 2n\pi \le x \le (2n + 1)\pi, n \in \mathbb{Z} \\ 0, & (2n - 1)\pi \le x \le 2n\pi, n \in mathbb{Z} \end{array}\right.</math>
<math>x \mapsto \left\lbrace \begin{array}{rl} \sin x, & 2n\pi \le x \le (2n + 1)\pi, n \in \mathbb{Z} \\ 0, & (2n - 1)\pi \le x \le 2n\pi, n \in \mathbb{Z} \end{array}\right.</math>


==Key data==
==Key data==

Latest revision as of 17:33, 22 September 2011

This article is about a particular function from a subset of the real numbers to the real numbers. Information about the function, including its domain, range, and key data relating to graphing, differentiation, and integration, is presented in the article.
View a complete list of particular functions on this wiki

Definition

This function of one variable, denoted sin+ is defined as the composite of the positive part function and the sine function.

Alternatively, it can be defined as the function max{sinx,0}

The function also has the following description using a piecewise definition:

x↦{sinx,2nπ≤x≤(2n+1)π,n∈Z0,(2n−1)π≤x≤2nπ,n∈Z

Key data

Item Value
domain all real numbers, i.e., all of R
range the closed interval [0,1]
absolute maximum value: 1, absolute minimum value: 0
period 2π
local maximum values and points of attainment 1, at number of the form 2nπ+π/2,n∈Z
local minimum values and points of attainment 0, at all points x in intervals of the form [(2n−1)π,2nπ], with n∈Z.
first derivative x↦{cosx,2nπ<x<(2n+1)π0,(2n−1)π<x<2nπ
The function is not differentiable at integer multiples of π. At even multiples of π, the left hand derivative is 0 and the right hand derivative is 1. At odd multiples of π, the left hand derivative is -1 and the right hand derivative is 0.
second derivative −sin+, except at integer multiples of π, where it is undefined.
mean value over a period 1/π