Question

9) If cus 9a = sin a and 90 < 90° then the value of tan 5a should be??
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Answer 1

Step-by-step explanation:

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Answer 2

Answer:

cos 9 a= sin a ( given)

cos 9a=cos(90-a)

cos 9a=cos90-cosa

cos10a= cos90

a=9

tan 5a=5×9=tan 45degree=1

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