【单选题】
已知直线过点<img class="kfformula" src="20190809/1565321501439277.png" data-latex="\left ( {\sqrt {3},-3} \right )"/>,且倾斜角为30°,则直线的方程是( )
①
<img src="20190809/1565321420131356.png" title="1565321420131356.png" alt="图片49.png"/>
②
<img src="20190809/1565321484569743.png" title="1565321484569743.png" alt="图片50.png"/>
③
<img src="20190809/1565321493966443.png" title="1565321493966443.png" alt="图片51.png"/>
④
<img src="20190809/1565321498657079.png" title="1565321498657079.png" alt="图片52.png"/>
【单选题】
SI模型的方程为
①
<img src=https://huaweicloudobs.ahjxjy.cn/9AFDEE36C1B07B225D2D722706CD1799.png title=1B94C_MOVTG]J~JS1EA0GGY.png alt=1B94C_MOVTG]J~JS1EA0GGY.png/>
②
<img src=https://huaweicloudobs.ahjxjy.cn/00C9306CA30D1D2DFAA1D847B6020370.png title=]K%D0W_2O8LU4}U)Z8$4$OJ.png alt=]K%D0W_2O8LU4}U)Z8$4$OJ.png/>
③
<img src=https://huaweicloudobs.ahjxjy.cn/D0D909306A10CF6DE1D31793AAAAB3E2.png title=EG0IKBM`3`%)H`@2V3}D5%B.png alt=EG0IKBM`3`%)H`@2V3}D5%B.png/>
【单选题】
下列方程中为常微分方程的是( )
①
<img src=https://huaweicloudobs.ahjxjy.cn/76EE3344F4B3F0A400C563E1B75A05C5.png title=[SEKXVFY5BOH_UDV{CX8M[1.png alt=[SEKXVFY5BOH_UDV{CX8M[1.png/>
②
<img src=https://huaweicloudobs.ahjxjy.cn/D2DA254C17523F281086022731C2A350.png title=DSX_H$AY$PVE[]DGSEMDT92.png alt=DSX_H$AY$PVE[]DGSEMDT92.png/>
③
<img src=https://huaweicloudobs.ahjxjy.cn/772A07E0D831407BCCD6B1F9D797AB76.png title=]}7)$G$DUS1LB24{_(9`R@X.png alt=]}7)$G$DUS1LB24{_(9`R@X.png/>
④
<img src=https://huaweicloudobs.ahjxjy.cn/46E6359E976B296C22C90C2B12285D14.png title=OH~JT`{B9@%]}CGWWIST`RK.png alt=OH~JT`{B9@%]}CGWWIST`RK.png/>