The Total solution for NCERT class 6-12
Prove the following results:
(i) Tan-1 (1/7) + tan-1 (1/13) = tan-1 (2/9)
(ii) Sin-1 (12/13) + cos-1 (4/5) + tan-1 (63/16)= π
(iii) tan-1 (1/4) + tan-1 (2/9) = Sin-1 (1/√5)
(i) Given Tan-1 (1/7)+ tan-1 (1/13) = tan-1 (2/9)
Hence, proved.
(ii) Given Sin-1 (12/13)+ cos-1 (4/5) + tan-1 (63/16) = π
Consider LHS
(iii) Given tan-1 (1/4)+ tan-1 (2/9) = Sin-1 (1/ √5)