Listen NCERT Audio Books - Kitabein Ab Bolengi
If , then is it true that ? Justify your answer.
Let in given triangle
Now, by using triangle law of vector addition,
As we can see that represent the sides of triangle.
Also we know that sum of two sides of a triangle must be greater than its third side.
is not true.
Write down a unit vector in XY-plane, making an angle of 30° with the positive direction of x-axis.
Find the scalar components and magnitude of the vector joining the points P(x1, y1, z1) and Q(x2, y2, z2).
A girl walks 4 km towards west, then she walks 3 km in a direction 30° east of north and stops. Determine the girl’s displacement from her initial point of departure.
Find the value of x for which is a unit vector.
Find a vector of magnitude 5 units, and parallel to the resultant of the vectors and
If , and , find a unit vector parallel to the vector .
Show that the points A(1, – 2, – 8), B(5, 0, –2) and C(11, 3, 7) are collinear, and find the ratio in which B divides AC.
Find the position vector of a point R which divides the line joining two points P and Q whose position vectors are externally in the ratio 1 : 2. Also, show that P is the midpoint of the line segment RQ.
The two adjacent sides of a parallelogram are and . Find the unit vector parallel to its diagonal. Also, find its area.
Show that the direction cosines of a vector equally inclined to the axes OX, OY and OZ are
Let and . Find a vector which is perpendicular to both a and , and
The scalar product of the vector a unit vector along the sum of vectors and is equal to one. Find the value of λ.
If are mutually perpendicular vectors of equal magnitudes, show that the vector is equally inclined to and
Prove that , if and only if are perpendicular, given .
If is the angle between two vectors and , then only when
Let and be two unit vectors and q is the angle between them. Then is a unit vector if
The value of is
If θ is the angle between any two vectors and , then when θ is equal to