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Question
If `tan θ = 9/40`, complete the activity to find the value of sec θ.
Activity:
sec2θ = 1 + `square` ...[Fundamental trigonometric identity]
sec2θ = 1 + `square^2`
sec2θ = 1 + `square`
sec θ = `square`
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Solution
sec2θ = 1 + \[\boxed{\text{tan}^2θ}\] ...[Fundamental trigonometric identity]
∴ sec2θ = 1 + \[\boxed{\frac{9}{40}}^2\]
∴ sec2θ = 1 + \[\boxed{\frac{81}{1600}}\]
∴ sec2θ = `1681/1600`
∴ sec θ = \[\boxed{\frac{41}{40}}\]
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