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प्रश्न
Choose the correct alternative:
cos θ. sec θ = ?
पर्याय
1
0
`1/2`
`sqrt(2)`
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उत्तर
1
cos θ. sec θ = cos θ. `1/"cos θ"` = 1.
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But `"AB"/"AC" = square and "BC"/"AC" = square`
∴ `sin^2 theta + cos^2 theta = square`
