Prove the identity, where the angles involved are acute angles for whi...
LHS:tanθ1−cotθ+cotθ1−tanθLHS:tanθ1-cotθ+cotθ1-tanθ
=tanθ1−cosθsinθ+cotθ1−sinθcosθ=tanθ1-cosθsinθ+cotθ1-sinθcosθ
=sinθcosθsinθ−cosθsinθ+cosθsinθcosθ−sinθcosθ=sinθcosθsinθ-cosθsinθ+cosθsinθcosθ-sinθcosθ
=sinθcosθ×sinθsinθ−cosθ+cosθsinθ×cosθcosθ−sinθ=sinθcosθ×sinθsinθ-cosθ+cosθsinθ×cosθcosθ-sinθ
=sin2θcosθ(sinθ−cosθ)+cos2θsinθ(cosθ−sinθ)=sin2θcosθ(sinθ-cosθ)+cos2θsinθ(cosθ-sinθ)
=sin2θcosθ(sinθ−cosθ)+cos2θsinθ(−sinθ+cosθ)=sin2θcosθ(sinθ-cosθ)+cos2θsinθ(-sinθ+cosθ)
=sin2θcosθ(sinθ−cosθ)−cos2θsinθ(sinθ−cosθ)=sin2θcosθ(sinθ-cosθ)-cos2θsinθ(sinθ-cosθ)
=1sinθ−cosθ(sin2θcosθ−cos2θsinθ)=1sinθ-cosθ(sin2θcosθ-cos2θsinθ)
=1sinθ−cosθ(sin3θ−cos3θsinθ.cosθ)=1sinθ-cosθ(sin3θ-cos3θsinθ.cosθ)
=1sinθ−cosθ×(sinθ−cosθ)(sin2θ+cos2θ+sinθ.cosθ)sinθ.cosθ=1sinθ-cosθ×(sinθ-cosθ)(sin2θ+cos2θ+sinθ.cosθ)sinθ.cosθ
=sin2θ+cos2θ+sinθ.cosθsinθ.cosθ=sin2θ+cos2θ+sinθ.cosθsinθ.cosθ
=1+sinθ.cosθsinθ.cosθ=1+sinθ.cosθsinθ.cosθ
=1sinθ.cosθ+sinθ.cosθsinθ.cosθ=1sinθ.cosθ+sinθ.cosθsinθ.cosθ
=1sinθ.cosθ+1=1sinθ.cosθ+1
=secθ.cosecθ+1=secθ.cosecθ+1
=1+sec&θ.cosecθ=RHS=1+sec&θ.cosecθ=RHSproved
Prove the identity, where the angles involved are acute angles for whi...
Proof:
To prove the given identity, we will start by expressing the expression in terms of sin and cos.
Let's first rewrite the expression on the left-hand side (LHS) of the equation:
LHS = (tanθ / (1 - cotθ)) * (cotθ / (1 - tanθ))
Now, we can rewrite tanθ and cotθ in terms of sinθ and cosθ:
tanθ = sinθ / cosθ
cotθ = cosθ / sinθ
Substituting these values into the expression, we get:
LHS = [(sinθ / cosθ) / (1 - (cosθ / sinθ))] * [(cosθ / sinθ) / (1 - (sinθ / cosθ))]
Simplifying further, we can rewrite this as:
LHS = [(sinθ / cosθ) / ((sinθ - cosθ) / sinθ)] * [(cosθ / sinθ) / ((cosθ - sinθ) / cosθ)]
Now, let's simplify each fraction separately:
LHS = [(sinθ / cosθ) * (sinθ / (sinθ - cosθ))] * [(cosθ / sinθ) * (cosθ / (cosθ - sinθ))]
LHS = [(sinθ * sinθ) / (cosθ * (sinθ - cosθ))] * [(cosθ * cosθ) / (sinθ * (cosθ - sinθ))]
LHS = [(sinθ * sinθ * cosθ * cosθ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))]
Notice that sinθ * cosθ = sinθ * (-sinθ) = -sin²θ
LHS = [(-sin²θ * cos²θ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))]
Using the identity: sin²θ + cos²θ = 1, we can substitute sin²θ with (1 - cos²θ):
LHS = [(-(1 - cos²θ) * cos²θ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))]
LHS = [(-cos²θ + cos⁴θ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))]
Simplifying the numerator further:
LHS = (-cos²θ + cos⁴θ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))
LHS = (cos⁴θ - cos²θ) / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))
Using the identity: cos²θ = 1 - sin²θ, we can substitute cos²θ with (1 - sin²θ):
LHS = [(1 - sin²θ) * (1 - sin²θ)] / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sinθ))
LHS = [1 - 2sin²θ + sin⁴θ] / (cosθ * sinθ * (sinθ - cosθ) * (cosθ - sin
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