Question 1070914
g(x) = cos(x)/x

g'(x) = (-sin(x)*x-cos(x))/x^2
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g'(pi/2) = (-1*(pi/2)/(pi^2/4)
m = -2/pi
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Line tangent at (pi/2,0):
y = (-2/pi)*(x - pi/2)
{{{y = -2x/pi + 1}}}