Please give solution of example 15. Example 15: Prove that sin θ - cos θ + 1 sin θ + cos θ - 1 = 1 sec θ - tan θ using the identity sec2 θ = 1 + tan2 θ . Share with your friends Share 0 Roopam Pandey answered this Dear student, Example 15: Prove that sinθ-cosθ+1sinθ+cosθ-1=1secθ-tanθTaking LHS , divide by cosθ in numerator and denominatorsinθ-cosθ+1sinθ+cosθ-1=sinθcosθ-cosθcosθ+1cosθsinθcosθ+cosθcosθ-1cosθ =tanθ+secθ-1tanθ-secθ+1 =tanθ+secθ-1tanθ-secθ+1 ×tanθ-secθtanθ-secθ =tanθ+secθtanθ-secθ-1×tanθ-secθtanθ-secθ+1tanθ-secθ =tan2θ-sec2θ-tanθ+secθtanθ-secθ+1tanθ-secθ1+tan2θ=sec2θ⇒sec2θ-tan2θ=1 =-1-tanθ+secθtanθ-secθ+1tanθ-secθ =-tanθ-secθ+1tanθ-secθ+1tanθ-secθ=-1tanθ-secθ =-1-secθ-tanθ=1secθ-tanθ =RHS Regards 0 View Full Answer