tan−1(1/3)\tan ^{-1}(1 / 3)tan−1(1/3)
tan−1(1/4)\tan ^{-1}(1 / 4)tan−1(1/4)
tan−1(3/5)\tan ^{-1}(3 / 5)tan−1(3/5)
tan−1(4/5)\tan ^{-1}(4 / 5)tan−1(4/5)
tan−1(3/4)\tan ^{-1}(3 / 4)tan−1(3/4)