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If sin(x)*tan(x) = 1, find cos(x).

 Dec 25, 2019

Best Answer 

 #1
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sin   *   sin/cos = 1

sin^2 / cos =1 

(1-cos^2) =cos

cos^2 + cos -1 = 0        Let    x = cos

x^2 + x -1 = 0    use quadratic formula to find  x = .618   or   -1.618   (throw out ...cos cannot be this magnitude)

 Dec 25, 2019
 #1
avatar+36916 
+1
Best Answer

sin   *   sin/cos = 1

sin^2 / cos =1 

(1-cos^2) =cos

cos^2 + cos -1 = 0        Let    x = cos

x^2 + x -1 = 0    use quadratic formula to find  x = .618   or   -1.618   (throw out ...cos cannot be this magnitude)

ElectricPavlov Dec 25, 2019

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