How to prove that
limx→∞exarccot(x)=∞?
I already figured that ddx[arrcot(x)]=ddx[arctan(1x)]=−1x2+1. Now I wanted to use L'Hospitals rule after doing some algebra:limx→∞exarccot(x)=limx→∞ex1arccot(x)=limx→∞ex1(x2+1)arccot2(x) using it twice didn't work out aswell, what am I supposed to do?
Answer
limx→∞arccotxe−x=limx→∞−11+x2−e−x=limx→∞ex1+x2
=limx→∞1+x+x22+x33!+O(x4)1+x2
Divide numerator & denominator by x2
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