If is surjective and A is finite, then B is finite. True or false?

I think this is false but my book says it is true.

I think its false by counter-example:

Let A= and let f(x) = tan(x). Then B is infinite?

Am I wrong about this?

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- July 4th 2011, 06:03 AMworc3247Question on a surjective map
If is surjective and A is finite, then B is finite. True or false?

I think this is false but my book says it is true.

I think its false by counter-example:

Let A= and let f(x) = tan(x). Then B is infinite?

Am I wrong about this? - July 4th 2011, 06:38 AMemakarovRe: Question on a surjective map
But your A is infinite as well despite the assumption.

- July 5th 2011, 08:53 AMMoeBleeRe: Question on a surjective map