Evaluate : \( \dfrac{sin \;18°}{cos\; 72°}\)

Asked by Abhisek | 1 year ago |  67

1 Answer

Solution :-

To simplify this, convert the sin function into cos function

We know that, 18° is written as 90° – 18°, 

which is equal to the cos 72°.

\( \dfrac{ sin (90° – 18°)}{cos \;72°}\)

Substitute the value, to simplify this equation

\( \dfrac{c os\; 72°}{cos \;72°}\) = 1

Answered by Pragya Singh | 1 year ago

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