Tricky Tricky little Identities

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SUMMARY

The discussion focuses on proving the trigonometric identity \( \frac{1}{1+\sin x} + \frac{1}{1-\sin x} = 2\sec^2 x \). The user initially struggles with simplifying the left side but receives guidance on the correct approach. The solution involves combining fractions and recognizing that \( 1 - \sin^2 x = \cos^2 x \), leading to the conclusion that the identity holds true. The final steps clarify the simplification process, confirming the identity.

PREREQUISITES
  • Understanding of trigonometric identities
  • Familiarity with fraction manipulation
  • Knowledge of the Pythagorean identity \( \sin^2 x + \cos^2 x = 1 \)
  • Basic algebraic skills for simplifying expressions
NEXT STEPS
  • Study advanced trigonometric identities and their proofs
  • Practice simplifying complex fractions in trigonometry
  • Learn about the Pythagorean identities in depth
  • Explore the applications of secant and cosecant functions in calculus
USEFUL FOR

Students studying trigonometry, educators teaching trigonometric identities, and anyone looking to improve their skills in solving trigonometric equations.

majinknight
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My friend sent me some Trigonometric proving identity questions to practise and i am usually good at them but i haven't done them for a while so i have gotten a bit rusty plus these ones to me are very difficult so i would like some assistance.
Prove 1/1+sin + 1/1-sinx = 2secsquaredx.
ok so left side looks hardest so i started with that and did it first. It may look confusing writing the divisions.

1/1+sinx + 1/1-sinx
1/1+ cosx/cotx + 1/cosx
cotx+1/cosx + 1/cosx
cotx+1/cosx + 1
cscx/cosx +1
Ok so that is where i have gotten to and it doesn't seem like i can get it to equal the right side. I think i have screwed up a step and i would like any assistance if possible. Please help
 
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You are making it look harder than it is... Just a 3 step problem.

\frac{1}{1+sinx} + \frac{1}{1-sinx} = \frac{2}{cos^2(x)}
\frac{2}{(1+sinx)(1-sinx)} = ...
\frac{2}{1 - sin^2(x)} = \frac{2}{cos^2(x)} = 2sec^2(x)
 
Oh you skipped step where you make bases same but you it works, thankyou very much.
 
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