Simplify 11+secθ+11−secθ.
Answer:
−2cot2θ
- Let,
S= 11+secθ+11−secθ - On adding two fractions,
⟹S=(1−secθ)+(1+secθ)(1+secθ)(1−secθ)⟹S=21−sec2θ - Using identity: sec2θ−1=tan2θ,
⟹S=2(−tan2θ)⟹S=−2cot2θ