SOLUTION: if sec x + cos x =5/2 then find the value of sec x - cos x

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Question 1035325: if sec x + cos x =5/2 then find the value of sec x - cos x
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
if sec x + cos x =5/2 then find the value of sec x - cos x
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Solve for cos(x)
sec x + cos x =5/2
1/cos + cos = 5/2
1 + cos^2 = 5cos/2
2cos^2 - 5cos + 2 = 0
(2cos - 1)(cos - 2) = 0
cos = 2 *********** no real solution, ignore
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cos = 1/2
--> sec = 1/cos = 2
--> sec - cos = 1.5