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BrittneyMarie
When you cough, your windpipe contracts. The speed, v, with which air comes out depends on the radius, r, of your windpipe. If R is the normal (at rest) radius of your windpipe, then for r<_(less than or equal to)R, the speed is given by: v=a(R-r)r^(2), where a is positive constant. What value of r maximizes the speed?
I assume so. Optimization it seems.
yes its calculus this section in the class was over linear approximations and differentials
Differentiate the given function equate your answer with zero ..solve the equation