begin mathsize $22$px style bold Which bold space bold the bold space bold following bold space bold is bold space bold one bold space bold to bold space bold one bold space bold function bold space bold space bold if bold space bold f bold colon bold real numbers bold rightwards arrow bold real numbers end style?

Select one:

f$($x$)=$begin mathsize $22$px style square root of bold x end style

f$($x$)=(1/$x$)-1$

f$($x$)=$x$2$

None of the above