Showing posts with label Straight line. Show all posts
Showing posts with label Straight line. Show all posts

Sunday, December 7, 2008

Definition of a straight line

A straight line is a curve such that every point on the line segment joining any two points on it lies on it.

every first degree equation in x,y represents a straight line.

Slope (Gradient) of a straight line

The general equation of a line is of the form ax +by +c = o and its slope is –a/b, provided b≠0.

Anlge between two straight lines

If m1 and m2 are the slopes of two lines, then the acute angle θ between them is given by tan θ = |m1-m2|/|1 + m1*m2|, provided m1*m2≠-1.

Intercepts of a line on the axes

If a straight line cuts x axis at A and O is origin AO or OA is the x-intercept.

If a straight line cuts y axis at B and O is origin BO or OB is the y-intercept.

Two lines - Point of intersection

Important properties and centres related to triangle

Centroid

Incentre

Circum-centre

Orthocentre

Friday, November 7, 2008

IIT JEE Study Guide 13. Cartesian System of Coordinates and Straight Lines - Revision Facilitator

1. Introduction

2. Catesian coordinate system

3. Distance between two points

4. Area of a triangle

5. Section Formulae

6. coordinates of the centroid, in-centre, and ex centre of a triangle

7. Locus and equation to a locus

8. Shifting of origin

9. Rotation of axes

10. Definition of a straight line

11. Slope (Gradient) of a straight line

12. Angle between two straight lines

13. Intercepts of a line on the axes

14. Equations of lines parallel to the coordinate axes

15. Different forms of the equation of a straight line

16. Transformation of general equation in different standard forms

17. point of intersection of two lines

18. Coordination of concurrency of three lines

19. Lines parallel and perpendicular to a given line

20. Angle between two straight lines when their equations are given.

21. Distance of a point from a line

22. Positions of points relative to a line

23. Equations of straight lines passing through a given point and making a given angle with a given line

24. Equations of the bisectors of the angles between two straight lines

25. Some important points of a triangle

26. Family of lines through the intersection of two given lines



Study Plan

Day 1

1. Introduction

2. Catesian coordinate system

3. Distance between two points

Day 2

4. Area of a triangle

5. Section Formulae

6. coordinates of the centroid, in-centre, and ex centre of a triangle

Day 3

7. Locus and equation to a locus

8. Shifting of origin


Day 4

9. Rotation of axes

10. Definition of a straight line

11. Slope (Gradient) of a straight line

12. Angle between two straight lines

Day 5

13. Intercepts of a line on the axes

14. Equations of lines parallel to the coordinate axes

15. Different forms of the equation of a straight line

Day 6

16. Transformation of general equation in different standard forms

17. point of intersection of two lines

18. Coordination of concurrency of three lines

Day 7

19. Lines parallel and perpendicular to a given line

20. Angle between two straight lines when their equations are given.

21. Distance of a point from a line

Day 8

22. Positions of points relative to a line

23. Equations of straight lines passing through a given point and making a given angle with a given line

Day 9

24. Equations of the bisectors of the angles between two straight lines

25. Some important points of a triangle

26. Family of lines through the intersection of two given lines - Up to Example 10

Day 10
26. Family of lines through the intersection of two given lines - Examples 21 to 30

Day 11
Illustrative Objective Type Examples 1 to 19

Day 12
Objective Type Exercise 1 to 20


Day 13
O.T.E. 21 to 40


Day 14
O.T.E. 41 to 60

Day 15
O.T.E. 61 to 80


Revision Period - 30 minutes a day

Day 16
O.T.E. 81 to 90


Day 17
O.T.E. 91 to 100


Day 18
O.T.E. 101 to 110


Day 19
O.T.E. 111 to 120



Day 20
O.T.E. 121 to 130



Day 21
O.T.E. 131 to 142


Day 22
Fill in the blanks type exercise 1 to 10


Day 23
Fill in the blanks type exercise 11 to 20


Day 24
Fill in the blanks type exercise 21 to 30

Day 25
Fill in the blanks type exercise 31 to 40


Day 26
True of False Exercise 1 to 19

Day 27
Practice Exercise 1 to 10

Day 28
Practice Exercise 11 to 20

Day 29
Practice Exercise 21 to 30

Day 30
31 to 41

Should you compulsorily do every problem. Not necessary. If you feel, you know how to do it, you can always skip some problems. But make a note of all difficult problems. You may have to a relook at them sometimes more to remember the complication or complexity in that problem.











Try to recollect relevant points on the topic.

If required right click on the topic and click on open in a new window to read the relevant material.

Close the window and come back.



Euclidean Geometry and Analytic Geometry - Difference

Distance between two points

Area of a triangle

Section Formulae

coordinates of the centres related to triangle

Definition of a straight line

Slope (Gradient) of a straight line

Angle between two straight lines

Intercepts of a line on the axes

Joint equation of a pair of straight lines

Saturday, June 7, 2008

Ch.13 Straight Lines - Revision Points 1

1. The equation of a line parallel to x-axis is of the form y = k.
The equation of a line parallel to y axis is of the form x = k, where k is a constant.

2. If a line makes an angle θ with the positive direction of x-axis and θ ≠π/2, then the slope of the line is given by tan θ.

3. the slope of a line passing through (x1,y1) and (x2,y2) is (y2-y1)/(x2-x1), provided x1≠x2.

4. If two lines have finite slopes m1 and m2
then they are parallel iff m1 = m2
they are perpendicular iff m1*m2 = -1

5. The equation of a line having slope m and y intercept c is y = mx+c

6. The equation of a line having slope m and passing through (x1,y1) is

(y-y1) = m(x-x1)

7. The equation of a line having slope m and passing through (x1,y1)and (x2,y2) is

(y-y1)/(x-x1) = (y1-y2)/(x1-x2)

8.The equation of a line making non-zero intercepts and b on the x and y axes respectively is

(x/a) + (y/b) = 1

9. The equation of a line such that the perpendicular drawn from the origin to the line has length p and inclination α is

x cos α + y sin α = p.

10. The general equation of a line is of the form ax +by +c = o and its slope is –a/b, provided b≠0.

11. If m1 and m2 are the slopes of two lines, then the acute angle θ between them is given by tan θ = |m1-m2|/|1 + m1*m2|, provided m1*m2≠-1.

12. The perpendicular distance of (x1,y1) from the line ax+by+c = 0 is given by |ax1 + by1 + c|/| √(a² + b²)|

13. The point of intersection of two lines, which are not parallel, can be found by solving their equations simultaneously.

14. Family of lines

If u ≡ a1x + b1y +c1 = 0 and
v≡ a2x +b2y +c2 = 0

the u + kv = 0, k Є R represents a family of lines

(i) if u and v are intersecting lines, then u + kv = 0, k Є R represents a family of lines passing through the point of intersection of u =0 and v=0.

(ii) if u and v are two parallel lines, u + kv = 0, k Є R represents a family of straight lines parallel to u =0 and v=0.