sec A + tan A = 3=> sec A= ?
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secA + tanA = 3
(1/cosA) + (sinA/cosA) = 3
(1 + sinA)/cosA = 3
1 + sinA = 3cosA
1 + sin²A + 2sinA = 9 - 9sin²A ( squaring andwriting cos²A as 1 - sin²A)
10sin²A + 2sinA - 8 = 0
applying Sridhar's formula we get that sinA = -1 or 0.8
when sinA = -1 cosA = 0 therefore at that time secA is undefined and thus this is not possible.
when sinA = 0.8 cosA = 0.6 and therefore secA = 1.6667
thus secA = 1.6667
(1/cosA) + (sinA/cosA) = 3
(1 + sinA)/cosA = 3
1 + sinA = 3cosA
1 + sin²A + 2sinA = 9 - 9sin²A ( squaring andwriting cos²A as 1 - sin²A)
10sin²A + 2sinA - 8 = 0
applying Sridhar's formula we get that sinA = -1 or 0.8
when sinA = -1 cosA = 0 therefore at that time secA is undefined and thus this is not possible.
when sinA = 0.8 cosA = 0.6 and therefore secA = 1.6667
thus secA = 1.6667
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