Saturday

April 19, 2014

April 19, 2014

Posted by **Tori** on Saturday, March 5, 2011 at 4:36pm.

- calculus -
**Reiny**, Saturday, March 5, 2011 at 6:14pmBelieve it or not, my crystal ball is working to today and I can "see" your illustration.

let the angle formed be Ø, then

dØ/dt = 4(2π) or 8π rad/min

tan Ø = x/(1/2)

tanØ = 2x

sec^2 Ø dØ/dt = 2 dx/dt

dx/dt = (sec^2 Ø)(dØ/dt)/2

when x = 2.5, tan Ø = 2.5/.5 = 5/1

then cosØ = 1/√26

secØ = (3x^4 + 6x^2 - 48x + 8)26

sec^2 Ø = 26

dx/dt = (26)(8π)/2 = 1004π miles/min

- calculus -
**Reiny**, Saturday, March 5, 2011 at 6:17pmthird last line should have been

sec Ø = √26

(on my Mac, I create √ by pressing "option" V, but I must have pressed "command" V, giving me a "cut-and -paste" of some previous post)

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