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  1. If sin θ + cos θ = p and sec θ + cosec θ = θ, then the value of θ (p² – 1) is
    1. 1
    2. p
    3. 2p
    4. 2
Correct Option: C

sin θ + cos θ = p
sec θ + cosec θ = q

1
+
1
= q
cos θsinθ

sinθ + cosθ
= q
sinθ . cosθ

∴ q(p² - 1) = sin θ + cos θ((sinθ + cosθ)² - 1)
sinθ . cosθ

=
sinθ + cosθ
. (sin²θ + cos²θ + 2sinθ.cosθ - 1)
sinθ . cosθ

=
sinθ + cosθ
. 2sinθ . cosθ
sinθ . cosθ

= 2p



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