# Important Formulas Of Trigonometric Ratios For RRB Stage – II

Mathematics is an equally important section for RRB Stage II exam and has an even more abundant importance in some other exams conducted by RRB & SSC. Generally, there are questions asked related to basic concepts and formulas of Ratio & Proportion.
To let you make the most of Mathematics section, we are providing important facts related to Mensuration . Also, Railway Exam Stage II is nearby with bunches of posts for the interested candidates in which Mathematics is a major part. We have covered important notes and questions focusing on these prestigious exams. We wish you all the best of luck to come over the fear of Mathematics section.

Trigonometry

Important Results :-
• If tan α.tan β = 1 then α + β = 90°
• If sin α.sec β = 1 then α + β = 90°
• If cos α.cosec β = 1 then α + β = 90°
• If cot α.cot β = 1 then α + β = 90°
• If sin α.cosec β = 1 then α + β = 180°
• sin² θ + cos² θ = 1 , sin² θ = 1  – cos² θ & cos² θ = 1 – sin² θ
• sec² θ – tan² θ = 1 , sec² θ = 1 + tan² θ & tan² θ = sec² θ – 1
• cosec² θ – cot² θ = 1 , cosec² θ = 1 + cot² θ & cot² θ = cosec² θ – 1
• If sin² α + sin² β = 2 or sin α + sin β = 2 , then α = β = 90°
• If sin² + cos² β = 2 or sin α + cos β = 2 , then α = 90° & β = 0°
• if cos² α + cos² β = 2 or cos α + cos β = 2 ,then α = β = 0°
• sin² α + sin² β = 0 when α = β = 0
• sin² α + cos² β = 0 when α = 0 & β = 90°
• cos² α + cos² β = 0 when α = β = 90°