Trig Help: Identifying Challenges & Solutions

Thread starter wajed
Start date Jun 11, 2009
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Trig

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Understanding the limitations of the arcsine function is crucial, as it only returns angles within the range of [-π/2, π/2], which can lead to confusion when dealing with sine values outside this interval. The discussion highlights that the equation sin(x) = sin(y) does not guarantee that x equals y, illustrated by the example of x = 0 and y = 2π. This emphasizes the importance of recognizing multiple angles that can yield the same sine value. Participants are encouraged to consider these nuances to avoid potential problems in trigonometric calculations. Mastering these concepts is essential for accurate problem-solving in trigonometry.

Jun 11, 2009

wajed

http://img132.imageshack.us/img132/8730/222fmf.jpg

what should I care of? what could cause problems to me?

Last edited by a moderator: May 4, 2017

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Jun 11, 2009

qntty

the principal value of arcsine is not a full inverse of sine. Arcsine returns an angle in [-pi/2,pi/2] but x can be any angle. The fact that you book reminded you of is equivalent to saying that sin(x)=sin(y) does not imply that x=y. Take x=0 and y=2*pi for example.

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