(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The 70N force acts on the end of the pipe at B. determine the angles theta between 0 and 180 of the force that will produce maximum and minimum moments about point A.

2. Relevant equations

FBD is attached.

3. The attempt at a solution

I made the following equation then took its derivative and put it equal to 0. The problem here is that I only get one value of theta. the one which gives the maximum value of the moment. there isn't any other value of tan coming withing 0-180. How do I get the minimum value of theta from this method. Wasn't I automatically supposed to get two value of theta from the first derivative and then I could I have gone further to second derivative to check if it was min or max. I am stuck.

Equation :- [tex]M = (70cos\theta * 0.9) + (70sin\theta * 0.7)[/tex]

Derivative :- [tex] = -63sin\theta + 49cos\theta [/tex]

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# Homework Help: Min and max value of moment

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