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(cosecθ + cosθ )2 + (secθ + sinθ)2 = ?​

User Zennon
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1 Answer

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Final answer:

To simplify the given expression, we expand and combine like terms. The expression (cosecθ + cosθ)^2 + (secθ + sinθ)^2 simplifies to 4 + 2sinθ/cosθ + 2cosθ/sinθ.

Step-by-step explanation:

To simplify the given expression, we expand and combine like terms:

Using the identity (a + b)^2 = a^2 + 2ab + b^2,

(cosecθ + cosθ)^2 + (secθ + sinθ)^2 = cosec^2θ + 2cosecθcosθ + cos^2θ + sec^2θ + 2secθsinθ + sin^2θ

Using the trigonometric identities cosecθ = 1/sinθ and secθ = 1/cosθ,

cosec^2θ + 2cosecθcosθ + cos^2θ + sec^2θ + 2secθsinθ + sin^2θ = (1/sin^2θ) + 2(1/sinθ)(cosθ) + cos^2θ + (1/cos^2θ) + 2(1/cosθ)(sinθ) + sin^2θ

Simplifying further,

(1/sin^2θ) + 2(1/sinθ)(cosθ) + cos^2θ + (1/cos^2θ) + 2(1/cosθ)(sinθ) + sin^2θ = 1/sin^2θ + 2cosθ/sinθ + cos^2θ + 1/cos^2θ + 2sinθ/cosθ + sin^2θ

Using the Pythagorean identities sin^2θ + cos^2θ = 1, we can simplify the expression further:

1/sin^2θ + 2cosθ/sinθ + cos^2θ + 1/cos^2θ + 2sinθ/cosθ + sin^2θ = 1/sin^2θ + 2cosθ/sinθ + 1 + 1/cos^2θ + 2sinθ/cosθ + 1

Combining like terms, we have:

(cosecθ + cosθ)^2 + (secθ + sinθ)^2 = 4 + 2sinθ/cosθ + 2cosθ/sinθ

User Neuronaut
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