Maths-
General
Easy

Question

If the sides a, b, c of a triangle are in G.P. and largest angle exceeds the smallest by 6 0 to the power of 0 end exponent, then c o s blank B equals

  1. 1    
  2. fraction numerator square root of 13 minus 1 over denominator 4 end fraction    
  3. fraction numerator 1 over denominator 2 end fraction    
  4. fraction numerator 1 minus square root of 13 over denominator 4 end fraction    

The correct answer is: fraction numerator square root of 13 minus 1 over denominator 4 end fraction


    a comma b comma c are in GP
    equals succeeds b to the power of 2 end exponent equals a c equals succeeds s i n to the power of 2 end exponent B equals blank s i n blankA s i n blank C
    equals 2 s i n to the power of 2 end exponent B equals blank c o s blank left parenthesis A minus C right parenthesis minus blank c o s blank left parenthesis A plus C right parenthesis
    equals 2 left parenthesis 1 minus c o s to the power of 2 end exponent B right parenthesis equals blank c o s blank 6 0 to the power of 0 end exponent minus blank c o s blank left parenthesis 18 0 to the power of 0 end exponent minus B right parenthesis

    Book A Free Demo

    +91

    Grade*

    Related Questions to study

    General
    physics-

    Two plane mirrors. A and B are aligned parallel to each other, as shown in the figure. A light ray is incident at an angle of 30 degree at a point just inside one end of A. The plane of incidence coincides with the plane of the figure. The maximum number of times the ray undergoes reflections (including the first one) before it emerges out is

    Two plane mirrors. A and B are aligned parallel to each other, as shown in the figure. A light ray is incident at an angle of 30 degree at a point just inside one end of A. The plane of incidence coincides with the plane of the figure. The maximum number of times the ray undergoes reflections (including the first one) before it emerges out is

    physics-General
    General
    physics-

    A point source of light B is placed at a distance L in front of the centre of a mirror of width d hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown. The greatest distance over which he can see the image of the light source in the mirror is

    A point source of light B is placed at a distance L in front of the centre of a mirror of width d hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown. The greatest distance over which he can see the image of the light source in the mirror is

    physics-General
    General
    physics-

    Figure shows a glowing mercury tube. The illuminances at point A, B and C are related as

    By the symmetry of the rays and location of the points.

    Figure shows a glowing mercury tube. The illuminances at point A, B and C are related as

    physics-General
    By the symmetry of the rays and location of the points.
    General
    physics-

    A block rests on a rough inclined plane making an angle  30 to the power of ring operatorof  with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block (in kg) is : open parentheses text  taken  end text g equals 10 ms squared close parentheses

    A block rests on a rough inclined plane making an angle  30 to the power of ring operatorof  with the horizontal. The coefficient of static friction between the block and the plane is 0.8. If the frictional force on the block is 10 N, the mass of the block (in kg) is : open parentheses text  taken  end text g equals 10 ms squared close parentheses

    physics-General
    General
    maths-

    In capital delta A B C space i f space c o s squared A plus c o s squared B plus c o s squared C equals 1 comma then the triangle is.

    A equals 3 0 to the power of 0 end exponent comma B equals 60 to the power of 0 end exponent comma C equals 90 to the power of 0 end exponent.

    In capital delta A B C space i f space c o s squared A plus c o s squared B plus c o s squared C equals 1 comma then the triangle is.

    maths-General
    A equals 3 0 to the power of 0 end exponent comma B equals 60 to the power of 0 end exponent comma C equals 90 to the power of 0 end exponent.
    General
    physics-

    Two masses straight m subscript 1 equals 5 kg text  and  end text straight m subscript 2 equals 4.8 Kg tied to a string are hanging over a light friction less pulley. What is the acceleration of the masses when they are free to move ? (g=9.8ms squared)

    Two masses straight m subscript 1 equals 5 kg text  and  end text straight m subscript 2 equals 4.8 Kg tied to a string are hanging over a light friction less pulley. What is the acceleration of the masses when they are free to move ? (g=9.8ms squared)

    physics-General
    General
    physics-

    A machine gun fires a bullet of mass 40 g with a velocity 1200 m s to the power of negative 1 end exponent . The man holding it, can exert maximum force of 144 N on the gun. How many bullets can he fire per second at the most?

    A machine gun fires a bullet of mass 40 g with a velocity 1200 m s to the power of negative 1 end exponent . The man holding it, can exert maximum force of 144 N on the gun. How many bullets can he fire per second at the most?

    physics-General
    General
    physics-

    One end of massless rope, which passes over a massless and frictionless pulley P is tied to a hook C while the other end is free. Maximum tension that the rope can bear is 840 N. With what value of maximum safe acceleration (in m s to the power of negative 2 end exponent ) can a man of 60 kg climb on the rope

    One end of massless rope, which passes over a massless and frictionless pulley P is tied to a hook C while the other end is free. Maximum tension that the rope can bear is 840 N. With what value of maximum safe acceleration (in m s to the power of negative 2 end exponent ) can a man of 60 kg climb on the rope

    physics-General
    General
    physics-

    Three identical blocks of masses m = 2 kg are drawn by a force F with an acceleration of 0.6 ms–2 on a frictionless surface, then what is the tension (in N) in the string between the blocks B and C

    Three identical blocks of masses m = 2 kg are drawn by a force F with an acceleration of 0.6 ms–2 on a frictionless surface, then what is the tension (in N) in the string between the blocks B and C

    physics-General
    General
    physics-

    When forces straight F subscript 1 comma straight F subscript 2 comma straight F subscript 3 are acting on a particle of mass m such that  and  are mutually perpendicular, then the particle remains stationary. If the force  is now removed then the acceleration of the particle is-

    When forces straight F subscript 1 comma straight F subscript 2 comma straight F subscript 3 are acting on a particle of mass m such that  and  are mutually perpendicular, then the particle remains stationary. If the force  is now removed then the acceleration of the particle is-

    physics-General
    General
    physics-

    In above problem, the value(s) of F for which M and m are stationary with respect tostraight M subscript 0

    In above problem, the value(s) of F for which M and m are stationary with respect tostraight M subscript 0

    physics-General
    General
    physics-

    Consider a special situation in which both the faces of the block straight M subscript 0  are smooth, as shown in adjoining figure. Mark out the correct statement(s)

    Consider a special situation in which both the faces of the block straight M subscript 0  are smooth, as shown in adjoining figure. Mark out the correct statement(s)

    physics-General
    General
    physics-

    Imagine a situation in which the horizontal surface of block straight M subscript 0 is smooth and its vertical surface is rough with a coefficient of friction mu  In above problem, choose the correct value(s) of F which the blocks M and m remain stationary with respect to M0

    Imagine a situation in which the horizontal surface of block straight M subscript 0 is smooth and its vertical surface is rough with a coefficient of friction mu  In above problem, choose the correct value(s) of F which the blocks M and m remain stationary with respect to M0

    physics-General
    General
    physics-

    Imagine a situation in which the horizontal surface of block straight M subscript 0 is smooth and its vertical surface is rough with a coefficient of friction  Identify  mu the correct statement(s)

    Imagine a situation in which the horizontal surface of block straight M subscript 0 is smooth and its vertical surface is rough with a coefficient of friction  Identify  mu the correct statement(s)

    physics-General
    General
    physics-

    A solid sphere of mass 10 kg is placed over two smooth inclined planes as shown in figure. Normal reaction at 1 and 2 will be open parentheses g equals 10 ms to the power of negative 2 end exponent close parentheses

    A solid sphere of mass 10 kg is placed over two smooth inclined planes as shown in figure. Normal reaction at 1 and 2 will be open parentheses g equals 10 ms to the power of negative 2 end exponent close parentheses

    physics-General