【单选题】
下列函数中既是奇函数又是增函数的是( )
①
img class=kfformula src=zzximg/20190808/1565254637543456.png data-latex=y=3x/
②
img class=kfformula src=zzximg/20190808/1565254637580775.png data-latex=y=\frac {1} {x}/
③
img class=kfformula src=zzximg/20190808/1565254637197572.png data-latex=y=2{x}^{2}/
④
img class=kfformula src=zzximg/20190808/1565254637194153.png data-latex=y=-\frac {1} {3}x/
【单选题】
下列函数中既是奇函数又是增函数的是( )
①
<img class="kfformula" src="20190808/1565254637580775.png" data-latex="y=\frac {1} {x}"/>
②
<img class="kfformula" src="20190808/1565254637194153.png" data-latex="y=-\frac {1} {3}x"/>
③
<img class="kfformula" src="20190808/1565254637543456.png" data-latex="y=3x"/>
④
<img class="kfformula" src="20190808/1565254637197572.png" data-latex="y=2{x}^{2}"/>