Stuck on math in deriving an optics equation

AI Thread Summary
The discussion revolves around deriving the formula for bright fringes in optics, with a focus on a specific mathematical approximation. The user is struggling with the expression (1+a)1/2 and seeks clarification on simplifying it to 1+a/2 when a is much smaller than 1. Examples provided demonstrate this approximation using small values of a, showing that the results are close to the expected values. The user expresses concern about the triviality of the question but is seeking assistance to move forward with their project. The conversation highlights the importance of understanding mathematical approximations in physics.
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Homework Statement



Hi. For a project I have to derive this formula for bright fringes in optics, but I'm stuck on this simple math part (or maybe its not so simple)...ive attached a picture of where i don't understand...it might be considered a simple math problem so I'm sorry if this is too trivial a question for physics forums :)

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(1+a)1/2 can be approximated by 1+a/2 if a<<1.

For example:

a=0.02: 1.021/2=1.00995...~1.01,

a=0.002: 1.0021/2=1.0009995...~1.001

ehild
 
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