Quick math question...

[Sage]

Okay, quick question for those of you calculus junkies... when you have a constant in front of a trig function, and you derive it, does anything happen to that constant?

For example, is the following correct?:

f(x) = -2sinx –> f'(x) = -2cosx

I know that if there's a constant, say, with the x, then you apply the power chain rule, but I've just never been sure what happens for the constant in front. BTW, I'm actually doing indefinite integrals now, so I should know this, but curse my terrible memory.

 

[Carl.]

It's correct

f = k x implies f ' = k x'

Yay, my first use of derivation skills after college a few years ago... ...well, maybe the 2nd or 3rd time. Still more useful than chemistry.

 

[Sage]

Thank you vedy much!

Chemistry's no fun... it's waay too easy (at the high school level anyway). And all the chem teachers here treat us like we can't do math (minus one point for not crossing out your units! ).

 

[Crayola]

Thats just above my level, I'm currently doing "advanced trig" but not calculous.

 

[Klostrophobic]

Originally posted by Sage
Thank you vedy much!

Chemistry's no fun... it's waay too easy (at the high school level anyway). And all the chem teachers here treat us like we can't do math (minus one point for not crossing out your units! ).

Haha, I hated having to write out the units in the actual problem. Then doing all the "work" step-by-step, when a trained monkey could make the leap from the question to the answer in one step.

It's almost as lame as notebook checks.

 

[Zrow]

Chemistry is ridiculous. We have this awful way of doing all of our problems, no matter what they are, using some kind of fractions. We must then cross out the units, and use significant figures, which makes the answer extremely vague and unreliable. The works is always some kind of multiplication or division problem, and could be done in one step. It makes me mad to think about all the time that we waste.

 

[Carl.]

Out of the three chemistry course I had in college, organic chemistry was the worst of all. (I was going in IT don't ask me why, they were mandatory courses....) do I want or will I ever need to know the formula of chlorobutan or what's an ester??

 

[Sage]

Originally posted by Klostrophobic
[...] It's almost as lame as notebook checks.

Oh, we have those in Chem too. In fact, last semester, we even had a "Notebook test". I swear, I have such a lame Chemistry teacher... (not my current one, who's been subbing for the past several months, but my "real" teacher comes back from maternity leave on May 1st. I dread that day's coming.)

Originally posted by Zrow
Chemistry is ridiculous. We have this awful way of doing all of our problems, no matter what they are, using some kind of fractions. We must then cross out the units, and use significant figures, which makes the answer extremely vague and unreliable. The works is always some kind of multiplication or division problem, and could be done in one step. It makes me mad to think about all the time that we waste.

Dimensional analysis?