Recent content by WalkingInMud

Op-Amp: "voltage-follower" question Hi all, ... If a simple op-amp circuit is described as: -> being in a "voltage-follower with-gain" configuration, and -> having a resistor ratio of 9:1 ...Where are the two resistors positioned with respect to the op-amp circuit element, and ...How...

Any Ideas on how to Approach this one? ... \int\sqrt{[1-sech(u)]^{2}+ [-tanh(u)sech(u)]^{2}}du We have a sech(u) and its derivative -tanh(u)sech(u) and this suggests some sort of substitution maybe, but the radical makes it a bit nasty for Me. Any Ideas? ...Thanks Heaps,

How does this look? r(t)=(t-tanht)i+(secht)j ...so r'(t)=(1-secht)i+(-tanhtsecht)j Now, secht is continuous for all real t, and also tanht is continuous for all real t, BUT... since tanh(0)=0 i.e. (-tanhtsecht)=0 for t=0, and furthermore sech(0)=1 i.e. (1-secht)=0 for t=0, ...r'(0)=0...

A parametric equation, say r(t), is smoothly parametrized if: 1. its derivative is continuous, and 2. its derivative does not equal zero for all t in the domain of r. Now that sounds simple enough. Now let's say we have the tractrix: r(t) = (t-tanht)i + sechtj, ... then r'(t) = [...

Let r(t) be a v.v.f -with the first and second derivatives r' and r''. Determine formula for d/dt [r.(r' x r'')] -in terms of r: How do we approach this one? maybe: d/dt [r.(r' x r'')] = d/dt [r.r' x r.r''] = ((r'.r' + r.r'') x r'.r'') + (r.r' x (r'.r'' + r.r''')) ?? ...and then what...