Please solve the question 6,7
Q.(vi) sin 60 ° - θ = cos ( 30 ° + θ )
[Hint. LHS = sin 90 ° - 30 ° + θ ]
(vii) sin θ sin 90 ° - θ + cos θ cos 90 ° - θ

Dear Student,

(vi) To prove: sin(60° - θ) = cos(30° + θ)Proof: LHS = sin(60° - θ) = cos(90° - (60° - θ)) = cos(90° - 60° + θ) = cos(30° + θ) = RHS. Hence, proved.               [cos(90° - θ) = sinθ](vii) sinθsin(90° - θ) + cosθcos(90° - θ)= sinθcosθ + cosθsinθ                                                [ sin(90° - θ) = cosθ, cos(90° - θ) = sinθ]= sin2θ + cos2θsinθcosθ= 1sinθcosθ                                                         [ sin2θ + cos2θ = 1]= cosecθsecθ= sec(90° - θ)cosec(90° - θ)                        [ sec(90° - θ) = cosecθ, cosec(90° - θ) = secθ]

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