Equation of the sphere whose center is on the Y axes and which passes through the points (1, - 2, 5) and (5, 1, - 4)
Equation of the sphere whose center is on the Y axes and which passes through the points (1, - 2, 5) and (5, 1, - 4) Correct Answer x<sup>2</sup> + y<sup>2</sup> + z<sup>2</sup> - 4y - 38 = 0
Let the equation of the sphere be
x2 + y2 + z2 + 2gx + 2fy + 2hz + d = 0
Since the center is on the Y axis, we have (0, 1, 0)i.e g = h = 0, y = 1
Hence equation of the sphere is
x2 + y2 + z2 + 2fy + d = 0
Since it passes through points (1, - 2, 5), (5, 1, - 4) we have
1 + 4 + 25 - 4f + d = 0
And 25 + 1 + 16 + 2f + d = 0
i.e 4f - d = 30
And 2f + d = - 42
Which gives f = - 2
Hence, d = - 38
So, equation of the sphere is
x2 + y2 + z2 - 4y - 38 = 0
মোঃ আরিফুল ইসলাম
Feb 20, 2025