Educator

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Example 1:

Prove the identity tan² x + 1 = sec² x.

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Example 2:

Given that tanθ = − 4.21 and (π/2) < θ < π , find secθ .

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Example 3:

Prove the following trigonometric identity:

cscθ − cotθ secθ − 1 = cotθ

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Example 4:

Prove the identity cot² x + 1 = csc² x.

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Example 5:

Given that secθ = (13/12) and 270^° < θ < 360^° , find tanθ .