हिंदी

Show that the points (i^-j^+3k^) and 3(i^+j^+k^) are equidistant from the plane r→⋅(5i^+2j^-7k^)+9 = 0 and lies on opposite side of it. - Mathematics

Advertisements
Advertisements

प्रश्न

Show that the points `(hati - hatj + 3hatk)` and `3(hati + hatj + hatk)` are equidistant from the plane `vecr * (5hati + 2hatj - 7hatk) + 9` = 0 and lies on opposite side of it.

योग

उत्तर

To show that these given points `(hati - hatj + 3hatk)` and `3(hati + hatj + hatk)` are equidistant from the plane `vecr * (5hati + 2hatj - 7hatk) + 9` = 0

And are equidastant from the plane,

We have to prove that midpoint of these points lies on the plane.

Now midpoint of the given points is `2hati + hatj + 3hatk`

On substituting vector(r) by the mid point in plane, we get 

L.H.S. = `(2hati + hatj + 3hatk) * (5hati + 2hatj - 7hatk) + 9`

= 10 + 2 – 21 + 9

= 0

= R.H.S.

Hence, the two points lie on opposite sides of the plane are equidistant form the plane.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 12: Introduction to Three Dimensional Geometry - Exercise [पृष्ठ २३७]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 12 Introduction to Three Dimensional Geometry
Exercise | Q 25 | पृष्ठ २३७

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Three vertices of a parallelogram ABCD are A (3, –1, 2), B (1, 2, –4) and C (–1, 1, 2). Find the coordinates of the fourth vertex.


Name the octants in which the following points lie: (5, 2, 3)


Name the octants in which the following points lie:

 (2, –5, –7) 


Find the image  of: 

 (–5, 0, 3) in the xz-plane. 


Planes are drawn parallel to the coordinate planes through the points (3, 0, –1) and (–2, 5, 4). Find the lengths of the edges of the parallelepiped so formed.


Prove that the point A(1, 3, 0), B(–5, 5, 2), C(–9, –1, 2) and D(–3, –3, 0) taken in order are the vertices of a parallelogram. Also, show that ABCD is not a rectangle.


Find the locus of P if PA2 + PB2 = 2k2, where A and B are the points (3, 4, 5) and (–1, 3, –7).


Are the points A(3, 6, 9), B(10, 20, 30) and C(25, –41, 5), the vertices of a right-angled triangle?


Verify the following: 

 (0, 7, –10), (1, 6, –6) and (4, 9, –6) are vertices of an isosceles triangle.


Verify the following:

 (5, –1, 1), (7, –4,7), (1, –6,10) and (–1, – 3,4) are the vertices of a rhombus.


Find the locus of the points which are equidistant from the points (1, 2, 3) and (3, 2, –1).


Write the distance of the point P(3, 4, 5) from z-axis.


Write the length of the perpendicular drawn from the point P(3, 5, 12) on x-axis.


What is the locus of a point for which y = 0, z = 0?


Find the point on y-axis which is at a distance of  \[\sqrt{10}\] units from the point (1, 2, 3).


The ratio in which the line joining (2, 4, 5) and (3, 5, –9) is divided by the yz-plane is


What is the locus of a point for which y = 0, z = 0?


The perpendicular distance of the point P (6, 7, 8) from xy - plane is


If the direction ratios of a line are 1, 1, 2, find the direction cosines of the line.


The x-coordinate of a point on the line joining the points Q(2, 2, 1) and R(5, 1, –2) is 4. Find its z-coordinate.


Find the image of the point having position vector `hati + 3hatj + 4hatk` in the plane `hatr * (2hati - hatj + hatk)` + 3 = 0.


Prove that the lines x = py + q, z = ry + s and x = p′y + q′, z = r′y + s′ are perpendicular if pp′ + rr′ + 1 = 0.


Find the equations of the line passing through the point (3,0,1) and parallel to the planes x + 2y = 0 and 3y – z = 0.


The plane ax + by = 0 is rotated about its line of intersection with the plane z = 0 through an angle α. Prove that the equation of the plane in its new position is ax + by `+- (sqrt(a^2 + b^2) tan alpha)z ` = 0


Show that the straight lines whose direction cosines are given by 2l + 2m – n = 0 and mn + nl + lm = 0 are at right angles.


If the directions cosines of a line are k, k, k, then ______.


The area of the quadrilateral ABCD, where A(0, 4, 1), B(2,  3, –1), C(4, 5, 0) and D(2, 6, 2), is equal to ______.


The angle between the planes `vecr.(2hati - 3hatj + hatk)` = 1 and `vecr.(hati - hatj)` = 4 is `cos^-1((-5)/sqrt(58))`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×