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Question
9 sec2 A − 9 tan2 A is equal to
Options
1
9
8
0
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Solution
Given:
`9 sec^2 A-9 tan^2 A`
`=9 (sec^2 A-tan^2 A)`
We know that, `sec^2 A-tan^2 A=1`
Therefore, `9 sec^2 A-9 tan^2 A=9`
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