Analytic Geometry Answers

. (a) The equation ax + by = 0 represents a line through the origin in R2. Show that the vector n1 = (a, b) formed from the coefficients of the equation is orthogonal to the line, that is, orthogonal to every vector along the line. (b) The equation ax + by + cz = 0 represents a plane through the origin in R3. Show that the vector n2 = (a, b, c) formed from the coefficients of the equation is orthogonal to the plane, that is, orthogonal to every vector that lies in the plane.

1. (Sections 2.3, 2.10, 2.11, 2.12) Let L1 be the line in R 3 with equation (x, y, z) = (1, 0, 2) + t(−1, 3, 4) ; t ∈ R and let L2 be the line that is parallel to L1 and contains the point (1, −1, 3). Let V be the plane that contains both the lines L1 and L2. (a) Find two vectors that are both parallel to the plane V but are not parallel to one another. (2) (b) Find a vector that is perpendicular to the plane V . (2) (c) Find an equation for the plane V . (2) (d) Find an equation for the line L3 that is perpendicular to the plane V and contains the point (1, −1, 4) . (2) Hint: Find a parametric equation for L3. Don’t try to find a Cartesian equation for L3. (Study Remarks 2.12.2.)

If 1, 1/2, 0 are direction ratios of a line, then the line makes an angle of 90° with the x-axis, an angle of 60° with the y-axis, and is parallel to the z-axis. State whether true or false, also give reason for your answer.

Ferris wheel cars are at a position of A (9,33) and B (27,-15). One of its axle is

represented by 3y+2x-7= 0 where it passes through the center of the wheel.

Draw the suitable graph of the said situation.

If A,B,C,D,P,Q are six distinct collinear points ,show that

(AP.AQ)/(AB.AC.AD)+(BP.BQ)/(BC.BD.BA)+(CP.CQ)/(CD.CA.CB)+(DP.DQ)/(DA.DB.DC)=0

Let e = (1, 0) and f = (1, 1) be two points in 

R2 . Find ix - yl, 12x - y I , where x = e + f, 

y = 2e + 2f