1.

If 3(cot2 ϕ – cos2 ϕ) = cos2 ϕ, 0° < ϕ < 90°, then the value of (tan2 ϕ + cosec2 ϕ + sin2 ϕ) is∶

A. 13/3
B. 25/12
C. 61/12
D. 15/4
Answer» D. 15/4


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