Recent content by DMac

Whoops sry guys, I'm still relatively new to the forum. My apologies.

You could probably use chain rule...as in: << complete solution deleted by berkeman >> Don't quote me on this, I'm still learning basic calculus.=D

Thanks to everyone who helped. I apologize for it seeming like I didn't do any work, but I'm not quite sure how to post pictures of my sketches. I'm just not that good at this whole technical stuff. I'll look into that the next time I have a problem like this. And about the poll...yeah my friend...

P.S. I'm not looking for an actual answer, I just need a pointer as to how to approach this problem.

[SOLVED] Optimizing the Area of a Triangle I've been doing countless other ones, but this one has really stumped me. "Triangle ABC has AB = AC. It is inscribed in a circle centre O, radius 10 cm. Find the value of the angle BAC that produces a maximum area for the triangle ABC." I've...

[SOLVED] Concavity of Trig Functions I'm working out a problem, but I'm stuck at a spot. The original equation is y = 2 cos x + sin 2x, and yes I did the second derivative, which came out to be cos x (4 sin x + 1) when i equate it to zero, i get cos x = 0 and 4 sin x + 1 = 0...

Ha, lolz I can't believe I didn't think of tan x = -1. (It's getting late, and I've only had 5 hours of sleep these past two nights.) Thanks for the help. =D

[SOLVED] Derivatives of Trigonometric Functions I need to find the critical numbers of this function: y = cos x - sin x where -pi <= x <= pi I found the derivative as: dy/dx = -(sin x + cos x) But when I equate dy/dx to zero, I get: sin x + cos x = 0...where do I go from here?

To EngageEngage: I know very basic vector analysis, like dot product, cross product, projections, direction cosines, etc. But that's pretty much it.

My textbook never covers equipotential lines =( ...One thing I don't understand is that I always thought that it would take no work to move a particle in the same direction as the field (isn't this true for magnetic fields?) ...so...lol I'm still confused.

(All I got from the expression for Work is I know that if those two vectors are perpendicular, then the dot product is zero. But...yeah I don't understand what those two vectors are exactly. Sorry)

I mean no disrespect, but I did not understand any of that because I'm still learning basic high school physics. (So, I don't know integration, or...lol anything, really.)

Is the question assuming that it's coming from air?

I have a few questions about electric potential and electric fields. If two points have the same electric potential, is it true that no work is required to move a test charge from one point to the other? Does that mean that no force is required as well? Also, How much work is required to...

Experimentally, you could probably use a spring setup where a spring is suspended vertically, and a mass is hung at the end. You measure the length of stretch of the spring, as well as the force applied to it (which is the weight of the mass). Doing multiple trials with different masses will...