Finding partial derivative of a trig function

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The discussion revolves around finding the partial derivative of the function sin(xyz - 1) with respect to x. The initial solution proposed was yz*cos(xyz - 1), but Wolfram Alpha provided yz*cos(1 - xyz). It was clarified that both expressions are equivalent due to the property of cosine being an even function. Users were encouraged to utilize the "Show steps" feature on Wolfram Alpha for better understanding. The conversation highlights common challenges faced by students returning to advanced mathematics after a break.
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Homework Statement



Find the partial derivative with respect to x of sin(xyz - 1)


Homework Equations



None needed.

The Attempt at a Solution



I took the answer to be yz*cos(xyz - 1), but wolfram alpha is giving me yz*cos(1 - xyz). Anyone know what's going on here? Thanks!
 
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cos(x) is equal to cos(-x)

Those answers are equivalent.

Btw, if you're confused as to what Wolfram Alpha is doing, press the "Show steps" button. Helps out sometimes.
 
Ah right I see, thanks a lot for clarifying that. I'm taking a senior level maths paper after 2 years of not doing maths, so I keep slipping up on things like that. Thanks again :)
 

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