If 3sec2 θ + tanθ - 7 =0, 0º < θ < 90º, then what is the value of ?
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Correct answer: A
Explanation
The correct answer is option 1 i.e. 5/4.
Given, 3sec2 θ + tanθ - 7 =0
Put θ = 45°
⇒ 3sec2 45°+ tan45° - 7 = 3 × 2 + 1 - 7 = 7 - 7 = 0
Thus, θ = 45° satisfies our given equation.
Put θ = 45° in
⇒ = (2sin45° + 3cos45°)/(cosec45° + sec45°)
⇒ {2 × (1/2)1/2 + 3 × (1/2)1/2}/{(2)1/2 + (2)1/2}
⇒ {5/(2)1/2}/{2 × (2)1/2} = 5/{2 × (2)1/2 × (2)1/2}
⇒ 5/4