How do you evaluate $arctan (\frac{1}{2}) + arctan (\frac{1}{3})$ $Arctan(1/2)+arctan(1/3)$ ?

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Answer 1 · 2016-07-12T16:34:31

$a r c tan 1$ $arc tan 1$ =pi/4, the principal against the principal values. The general value is $npi+pi/4, n=0, +-1, +-2. +-3,...$

Use tan ( a + b )=( tan a + tan b )/( 1 - tan a tan b).

Here, the tangent of the sum of the angles #=(1/2+1/3)/(1-(1/2)(1/3))=1.

Answer is the inverse $tan^(-1) 1$ . Now, see the answer. again.

How do you evaluate Arctan(1/2)+arctan(1/3)arctan(12)+arctan(13)Arctan(1/2)+arctan(1/3)?