Question

. Write the value of 2 cos2 15° - 1.
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Answer 1

Answer:

Value of 2cos²15° - 1 = √3/2

Step-by-step explanation:

/* we know that 2cos²A-1 = cos2A */

Now ,

Value of 2cos²15° - 1

= cos(2×15)

= cos 30°

= √3/2

Therefore,

Value of 2cos²15° - 1 = √3/2

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