Select Board
CBSE Classes
If tan A = 5/6, tan B = 1/11, prove that A + B = π/4.
tan A = 5/6, tan B = 1/11
tan (A + B) = (tan A + tan B) / (1 - tan A tan B)
= (5/6 + 1/11) / (1 - (5/6)(1/11))
= (55 + 6/61) / (66 - 5/61)
= 61/61 = 1
⇒ A + B = π/4