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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 + tan2θ ......[Fundamental trigonometric identity]
∴ sec2θ = 1 + `(9/40)^2`
∴ sec2θ = 1 + `81/1600`
∴ sec2θ = `1681/1600`
∴ sec θ = `41/40`
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