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प्रश्न
Write the value of cosec2 (90° − θ) − tan2 θ.
उत्तर
We have,
`cosec^2 (90°-θ)- tan ^2θ= {cosec(90°-θ)}^2-tan ^2θ`
= `(secθ )^2-tan^2 θ`
= `sec^2 θ-tan ^2 θ`
We know that, ` sec^2 θ-tan ^2θ=1`
Therefore, \[{cosec}^2 \left( 90° - \theta \right) - \tan^2 \theta = 1\]
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