【单选题】
下列函数中,在区间<img class="kfformula" src="20190808/1565255863544549.png" data-latex="\left ( {-\infty ,+\infty } \right )"/>内为增函数的是( )
①
<img class="kfformula" src="20190808/1565255863279980.png" data-latex="y=2-x"/>
②
<img class="kfformula" src="20190808/1565255863845028.png" data-latex="y={3}^{x}"/>
③
<img class="kfformula" src="20190808/1565255863797150.png" data-latex="y={x}^{-2}"/>
④
<img class="kfformula" src="20190808/1565255863844363.png" data-latex="y={log}_{0.3}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=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}"/>
【单选题】
下列函数中,在区间img class=kfformula src=zzximg/20190808/1565255863544549.png data-latex=\left ( {-\infty ,+\infty } \right )/内为增函数的是( )
①
img class=kfformula src=zzximg/20190808/1565255863845028.png data-latex=y={3}^{x}/
②
img class=kfformula src=zzximg/20190808/1565255863797150.png data-latex=y={x}^{-2}/
③
img class=kfformula src=zzximg/20190808/1565255863279980.png data-latex=y=2-x/
④
img class=kfformula src=zzximg/20190808/1565255863844363.png data-latex=y={log}_{0.3}x/