Mathc initiation/a0076
Calculons la dérivée :
y = cot(x)
y = cos(x)/sin(x)
y'= ( cos(x)/sin(x) )'
y'= -sin(x)sin(x) - cos(x)cos(x)
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sin(x)**2
y'= -[sin(x)**2 + cos(x)**2]
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sin(x)**2
y'= -1
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sin(x)**2
y'= -csc(x)**2