SOLUTION: Solve: sec^2x + tan^2x=7

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Question 1189409: Solve: sec^2x + tan^2x=7
Answer by Alan3354(69443) About Me  (Show Source):
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Solve: sec^2x + tan^2x=7
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1/cos^2 + sin^2/cos^2 = 7
1 + sin^2 = 7cos^2 = 7(1- sin^2) = 7 - 7sin^2
8sin^2 = 6
sin^2 = 3/4
sin(x) = sqrt(3)/2
x = pi/3, 2pi/3 + n*2pi (n is an integer)
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sin(x) = -sqrt(3)/2
x = 4pi/3, 5pi/3 + n*2pi