My Math Forum

My Math Forum (http://mymathforum.com/math-forums.php)
-   Calculus (http://mymathforum.com/calculus/)
-   -   stationary points of a trig function (http://mymathforum.com/calculus/343130-stationary-points-trig-function.html)

DomB December 23rd, 2017 05:28 AM

stationary points of a trig function
 
Hi, am I doing this right?

Find the coordinates when the gradient of this function is equal to zero

t = cos(θ)

f '(t) = -sin(θ)
$\ \ \ \ \ \ \ \ $ = -sin(θ) = 0
$\ \ \ \ $ θ = 0/-sin
$\ \ \ \ $ θ = 0


Plug 0 in to original equation
t = cos(0)
t = 1
Coordinates = 0,1 where gradient is zero.

greg1313 December 23rd, 2017 06:13 AM

$\sin\theta$ is periodic.

skipjack December 23rd, 2017 09:30 AM

Having obtained -sin(θ) = 0, one cannot divide by "-sin".

Instead, solve sin(θ) = 0 by using knowledge of the sin function.


All times are GMT -8. The time now is 07:47 AM.

Copyright © 2018 My Math Forum. All rights reserved.