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rainbow22
find limit to infinity 4x sin (1/x) Answer is 4
multiply by (1/x)/(1/x)
Or define y=1/x where y tends to 0, and you get the basic limit of (sin x)/x
Can you please show me how to do it?
that is it, there is nothing else, it is know that lim when y -> 0 of (sin x)/x is 1: look at the picture.|dw:1347580779959:dw|
The arc lenght and the sin get praticaly equal, and in the limit they coincide, when you substitute what I said you get this limit, wich is 1, times 4.