19. sin20
sec 70+cos 25
cosec 65=
Answers
Answered by
1
Given : sin20°.sec70°+cos25°.cosec65°
To Find : Value
Solution:
sin20°.sec70°+cos25°.cosec65°
Sec x = 1/Cosx
cosec x = 1/sinx
= sin20°/cos70°+cos25°/Sin65°
Sin ( 90° - x) = Cosx
Cos ( 90° - x) = Sinx
Cos 70° = Cos (90° - 20°) = Sin 20°
Sin65° = Sin ( 90° - 25°) = Cos 25°
= Sin 20° / Sin 20° + Cos 25°/Cos 25°
= 1 + 1
= 2
Hence sin20°.sec70°+cos25°.cosec65° = 2
Learn More
if a=60° and b=30°, find the value of (sin a cos b + cos a sin b) ^2
brainly.in/question/7852027
If sin theta -cos theta =1/2.then find the value of 1/sintheta+cos theta ...
brainly.in/question/2093405
Similar questions