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Use basic identities to simplify the expression. one divided by cotangent of theta to the second power. + sec θ cos θ

User IlyaSurmay
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we are asked in the problem to simplify the expression one divided by cotangent of theta to the second power. + sec θ cos θ. the first term is expressed as tan2 θ. sec theta is the inverse of cos θ in which the second term is equal to 1. tan2 θ + 1 is equal to sec2 θ
User Rameswar Prasad
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Answer:

The simplified expression is:


(1)/(\cot^2 \theta)+\sec \theta\cos \theta=\sec^2 \theta

Explanation:

We are asked to simplify the expression:

one divided by cotangent of theta to the second power+ sec θ cos θ

i.e. mathematically it is written as:


=(1)/(\cot^2 \theta)+\sec \theta\cos \theta

We know that:


\tan \theta=(1)/(\cot \theta)\\\\i.e.\\\\(\tan \theta)^2=((1)/(\cot \theta))^2\\\\i.e.\\\\\tan^2 \theta=(1)/(\cot^2 \theta)

Hence, we can write this expression as:


(1)/(\cot^2 \theta)+\sec \theta\cos \theta=\tan^2 \theta+\sec \theta\cos \theta

Also, we know that:


\sec \theta=(1)/(\cos \theta)

Hence, we have:


\sec \theta\cos \theta=(\cos \theta)/(\cos \theta)\\\\\\i.e.\\\\\\\sec \theta\cos \theta=1

Hence, we get:


=(1)/(\cot^2 \theta)+\sec \theta\cos \theta=\tan^2 \theta+1

Also, we know that:


\sec^2 \theta-\tan^2 \theta=1\\\\i.e.\\\\\sec^2 \theta=1+\tan^2 \theta

Hence, we get the simplified expression as:


(1)/(\cot^2 \theta)+\sec \theta\cos \theta=\sec^2 \theta

User Benteh
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