Question No. 8,Question No. 10,Question No. 11,Question No. 13,Question No. 14

Lesson#4
Toolkit for Exercise 9.4
Prove the following identity:
Q6: cot^2 θ−cos^2 θ=cot^2 θ .cos^2 θ
Question No. 8
Q8: 2 cos^2 θ−1=1−2 sin^2 θ
Q9: cos^2 θ−sin^2 θ=(1−tan^2 θ" " )/(1+tan^2 θ" " )
Question No. 10
Q10: (cosθ−sinθ)/(cosθ+sinθ)=(cotθ−1)/(cotθ+1)
Question No. 11
Q11: (sin θ)/(1+cos θ)+cot θ=cosec θ
Question No. 13
Q13: (1+cosθ)/(1−cosθ)=(cosecθ+cotθ)^2
Question No. 14
Q14: (secθ−tanθ)^2=(1−sinθ)/(1+sinθ)
Q15: (2 tanθ)/(1+tan^2 θ)=2 sinθ cosθ
Exercise No. 9.4
Chapter No.9
Fundamentals of Trignometry
maths
part 1