Maths question

c0mplex SG

If {a_n} converges to L, does it mean that |{a_n}| also converges to |L|? If yes, why?

nukewatch SG

If L < 0, how does |{a_n}| converges to L?

c0mplex SG

ops... should be |L|... sorry for the typo Embarassed

greengoblin SG

Use triangular inequality. If you are doing real analysis, this should be a standard weapon in your arsenal.

c0mplex SG

i tried... but don't know how to continue... Confused

greengoblin SG

Go and prove
||{a_n}| - |L|| < |{a_n} - L| < e

c0mplex SG

ahh..... i know how le... Very Happy i keep thinking about the 'normal' triangle inequality... i forgot about the reverse triangle inequality... Razz thanks Surprised