Solving for F(x) = 1 / (sec x) + cos x

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SUMMARY

The discussion focuses on simplifying the function F(x) = 1 / (sec x) + cos x within the interval 0 < x < π/2. Participants confirm that substituting (1 + tan² x)^(1/2) with sec² x is a valid approach. The simplification leads to the conclusion that F(x) ultimately equals zero, as the terms cancel each other out. The discussion also hints at a similar problem involving the interval π < x < 3π/2, indicating the need for careful consideration of function behavior across different intervals.

PREREQUISITES
  • Understanding of trigonometric identities, specifically secant and cosine functions.
  • Familiarity with the Pythagorean identity: 1 + tan² x = sec² x.
  • Basic knowledge of function simplification techniques in calculus.
  • Ability to analyze function behavior over specified intervals.
NEXT STEPS
  • Study the properties of trigonometric functions in different quadrants.
  • Learn about the implications of function simplification in calculus.
  • Explore advanced trigonometric identities and their applications.
  • Investigate similar problems involving function behavior across various intervals.
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Students and educators in mathematics, particularly those focusing on trigonometry and calculus, as well as anyone looking to enhance their problem-solving skills in function simplification.

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problem: Simplify F(x) = 1 / ( 1+tan^2 x)^.5 - cos x :0<x<pi/2

ok the only thing i can think of to substitute in was (1+tan^2 x)^.5 = sec^2 x ...

so i got the problem down to 1 / (sec^2 x)^.5 + cos and then become stucks

i m thinken i can just say it is 1 / (sec x) + cos... not sure if that will work or not

thanks in advance for any help
 
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You're on the right track...here's a hint: 1\secx = cosx
 
ya but then cos x - cos x = 0...

(i had actually worked it out using that but i didn't think the answer would be zero... esp since the next problem is the same the only differnce is that it is from pi < x < 3 pi / 2)

i guess i just needed a second untainted opion... thanks
 
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