\$fcolonsdrta.netbb R^+ osdrta.netbb R^+\$, \$f(x) = x^2\$ is injective.\$fcolonsdrta.netbb R osdrta.netbb R\$, \$f(x) = x^2\$ is not injective given that \$(- x)^2 = x^2\$.

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what is the difference between \$sdrta.netbb R^+\$ and \$sdrta.netbb R\$?

Furthermore, what is the distinction between \$sdrta.netbb N\$ and also \$sdrta.netbb N^+\$?  \$sdrta.netbb R^+\$ commonly denotes the set of positive actual numbers, that is: \$\$sdrta.netbb R^+ = xinsdrta.netbb Rmid x>0\$\$

It is also deprovided by \$sdrta.netbb R^>0,sdrta.netbb R_+\$ and so on.

For \$sdrta.netbb N\$ and \$sdrta.netbb N^+\$ the difference is comparable, however it might be non-existent if you define \$0 otinsdrta.netbb N\$. In many kind of collection concept publications \$0\$ is a natural number, while in analysis it is regularly not thought about a herbal number. Your mileage might vary on \$sdrta.netbb N\$ vs. \$sdrta.netbb N^+\$. Simply \$sdrta.netbb R\$ suggests the set of real numbers.

\$sdrta.netbb R^+\$ suggests the set of positive genuine numbers.

And \$sdrta.netbb R^-\$ implies the set of negative genuine numbers. Thanks for contributing a solution to sdrta.netematics Stack Exchange!

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Use sdrta.netJax to format equations. sdrta.netJax recommendation.

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What is the distinction in between \$sdrta.netcalXsubseteqsdrta.netbbR^n\$ and also \$sdrta.netcalXsubsetsdrta.netbbR^n\$
Cyclic groups: What is the distinction between \$sdrta.netbbZ_n\$, \$sdrta.netbbZ_n^*\$ and \$sdrta.netbbZ_n^+\$? 