Q. 2 E

Let us show that:

sec70°sin20° + cos20°cosec70° = 2

Answer :

Given, sec70°sin20° + cos20°cosec70° = 2


Need to prove the given equation as two


we know that sec(90 - θ) = cosecθ and cosec(90 - θ) = secθ


sec70° = sec(90 - 20)°


= cosec20° - - - eq (1)


And cosec70° = cosec(90 - 20)


= sec20° - - - - - eq(2)


Substitute eq(1) and eq(2) in the given equation


cosec20°sin20° + cos20°sec20° = 2



[ and ]


= 2


2 = 2


Hence, proved


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Quiz | Task on Trigonometric Ratios46 mins
T- Ratios of Specified Angles58 mins
Quiz on Trigonometric Ratios31 mins
Trigonometric Identities33 mins
Champ Quiz | Trigonometric Identities33 mins
Testing the T- Ratios of Specified Angles57 mins
NCERT | Trigonometric Identities52 mins
Trigonometric Identities44 mins
Trick to learn all Trigonometric Formulae28 mins
Solving NCERT Questions on Trigonometric Identities56 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses