1. Three-dimensional space is defined by x = 0 and z = 0 which forms the y-axis. The distance of a point (p, q, r) from the y-axis is computed by its x and z coordinates because the y-axis does not have any displacement in the x or z direction. Therefore, the distance is the perpendicular distance of tRead more

    Three-dimensional space is defined by x = 0 and z = 0 which forms the y-axis.
    The distance of a point (p, q, r) from the y-axis is computed by its x and z coordinates because the y-axis does not have any displacement in the x or z direction.

    Therefore, the distance is the perpendicular distance of the point from the yaxis, that is given by
    √(p² + r²)

    So, the correct answer is: √(p² + r²)

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  2. A line parallel to the z-axis has constant x and y coordinates, while the z-coordinate changes. For a line passing through the point (1, 1, 1) and parallel to the z-axis, the x and y coordinates remain constant at 1, while the z-coordinate changes. The parametric equation of the line is: (x - 1)/0 =Read more

    A line parallel to the z-axis has constant x and y coordinates, while the z-coordinate changes. For a line passing through the point (1, 1, 1) and parallel to the z-axis, the x and y coordinates remain constant at 1, while the z-coordinate changes.

    The parametric equation of the line is:

    (x – 1)/0 = (y – 1)/0 = (z – 1)/1

    Thus, the correct answer is:
    (x – 1)/0 = (y – 1)/0 = (z – 1)/1

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  3. The given equations of the lines can be written in parametric form: For the first line: 2x = 3y = -z, let the parameter be t. x = t/2, y = t/3, z = -t. For the second line: 6x = -y = -4z, let the parameter be s. x = s/6, y = -s, z = -s/4. The direction ratios of the first line are (1/2, 1/3, -1) andRead more

    The given equations of the lines can be written in parametric form:

    For the first line:
    2x = 3y = -z, let the parameter be t.
    x = t/2, y = t/3, z = -t.

    For the second line:
    6x = -y = -4z, let the parameter be s.
    x = s/6, y = -s, z = -s/4.

    The direction ratios of the first line are (1/2, 1/3, -1) and the direction ratios of the second line are (1/6, -1, -1/4).

    The angle θ between two lines is given by the formula:
    cos θ = (l₁l₂ + m₁m₂ + n₁n₂) / √(l₁² + m₁² + n₁²) * √(l₂² + m₂² + n₂²)

    Substitute the values:
    cos θ = [(1/2)(1/6) + (1/3)(-1) + (-1)(-1/4)] / √[(1/2)² + (1/3)² + (-1)²] * √[(1/6)² + (-1)² + (-1/4)²]

    Simplifying this expression results in cos θ = 0, so the angle θ = 90°.

    Thus, the correct answer is: 90°

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  4. The direction cosines of a line are the cosines of the angles it makes with the x, y, and z axes. Given the angles: - θ₁ = 90° with the x-axis, so cos(θ₁) = 0 - θ₂ = 135° with the y-axis, so cos(θ₂) = -1/√2 - θ₃ = 45° with the z-axis, so cos(θ₃) = 1/√2 Thus, the direction cosines are: 0, -1/√2, 1/√2Read more

    The direction cosines of a line are the cosines of the angles it makes with the x, y, and z axes.

    Given the angles:
    – θ₁ = 90° with the x-axis, so cos(θ₁) = 0
    – θ₂ = 135° with the y-axis, so cos(θ₂) = -1/√2
    – θ₃ = 45° with the z-axis, so cos(θ₃) = 1/√2

    Thus, the direction cosines are:
    0, -1/√2, 1/√2

    Therefore, the correct answer is:
    0, -1/√2, 1/√2

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  5. The direction ratios of the two lines are given as: Line 1: a², b², c² Line 2: b² - c², c² - a², a² - b² The angle θ between two lines is given by the formula: cos θ = (l₁l₂ + m₁m₂ + n₁n₂) / √(l₁² + m₁² + n₁²) * √(l₂² + m₂² + n₂²) Substituting the direction ratios into the formula: cos θ = [(a²)(b²Read more

    The direction ratios of the two lines are given as:
    Line 1: a², b², c²
    Line 2: b² – c², c² – a², a² – b²

    The angle θ between two lines is given by the formula:

    cos θ = (l₁l₂ + m₁m₂ + n₁n₂) / √(l₁² + m₁² + n₁²) * √(l₂² + m₂² + n₂²)

    Substituting the direction ratios into the formula:

    cos θ = [(a²)(b² – c²) + (b²)(c² – a²) + (c²)(a² – b²)] / √[(a²)² + (b²)² + (c²)²] * √[(b² – c²)² + (c² – a²)² + (a² – b²)²]

    After simplifying the expression, we get cos θ = 0, which means θ = π/2.

    Thus, the correct answer is: π/2

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