Question

# At θ=90∘, which of the two angles are not defined? cot θ,sin θ tan θ,cosec θ cot θ,tan θ tan θ,sec θ

Solution

## The correct option is D tan θ,sec θ As tan θ=sin θcos θ and at θ=90∘,cos 90∘=0. So, tan θ is not defined. Similarly, sec θ=1cos θ. So, sec θ is not defined at  θ=90∘.

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