多选题Which of the following equations are for lines which are perpendicular to the line y=2x+4?A2y +x = 5B2y –x = 3Cx + 2y = 7Dx – 2y = 4E4y +2x = 0
多选题
Which of the following equations are for lines which are perpendicular to the line y=2x+4?
A
2y +x = 5
B
2y –x = 3
C
x + 2y = 7
D
x – 2y = 4
E
4y +2x = 0
参考解析
解析:
直线y=2x+4的斜率为2,所以与其垂直的直线的斜率为-1/2,故本题选择ACE三项。
直线y=2x+4的斜率为2,所以与其垂直的直线的斜率为-1/2,故本题选择ACE三项。
相关考题:
以下程序段运行结束后,变量X的值为( )。 X=2Y=4DoX=x*yY=y+lLoop While y 以下程序段运行结束后,变量X的值为( )。 X=2Y=4DoX=x*yY=y+lLoop While yA.2B.4C.8D.20
假设X、Y两个变量分别表示不同类型借款人的违约损失,其相关系数为0.3,若同时对X、Y作相同的线性变化Xt=2X。Y,=2Y。则X1和Y1的相关系数为( )。A.O.3B.O.6C.0.O9D.O.15
过点P(2,-3)且在两坐标轴上截距相等的直线方程是( )A.χ+y+1=0或3χ+2y=0B.χ-y-1=0或3χ+2y=0C.χ+y-1=0或3χ+2y=0D.χ-y+1=0或3χ+2y=0
具有待定特解形式为y=A1x+A2+B1ex的微分方程是下列中哪个方程()?A、y″+y′-2y=2+exB、y″-y′-2y=4x+2exC、y″-2y′+y=x+exD、y″-2y′=4+2ex
单选题具有特解y1=e-x,y2=2xe-x,y3=3ex的三阶常系数齐次线性方程是( )。Ay‴-y″-y′+y=0By‴+y″-y′-y=0Cy‴-6y″+11y′-6y=0Dy‴-2y″-y′+2y=0
单选题以y1=ex,y2=e-3x为特解的二阶线性常系数齐次微分方程是( )。[2012年真题]Ay″-2y′-3y=0By″+2y′-3y=0Cy″-3y′+2y=0Dy″-2y′-3y=0
单选题For which of the following equations is x = -2 a root?I. 2/x-4II. x2 + 4=0III. x2 + 4x +4 = 0AI onlyBII onlyCIII onlyDI and IIIEII and III
单选题具有待定特解形式为y=A1x+A2+B1ex的微分方程是下列中哪个方程()?Ay″+y′-2y=2+exBy″-y′-2y=4x+2exCy″-2y′+y=x+exDy″-2y′=4+2ex
单选题Line l passes through the origin and is perpendicular to the line given by the equation 2x + y = 8. Which of the following points is NOT on line l?A(-4, -2)B(-1,1)C(2,1)D(4,2)E(7,3.5)
单选题设y=ex(c1sinx+c2cosx)(c1、c2为任意常数)为某二阶常系数线性齐次微分方程的通解,则该方程为( )。Ay″+2y′+2y=0By″-2y′+2y=0Cy″-2y′-2y=0Dy″+2y′+2y=0