The number of a point on the circle 2x² 2y²-3x=0 which are at a distan...
The locus of all points which are at a distance 2 units from (-2,1) is a circle. So, let us assume a circle with center at (-2,1) and radius 2 and then find whether this circle intersects the given circle or not. If it intersects then the of points of intersection are the required points.
As the circles are not intersecting, there will be no points which are on the given circle and at a distance 2 units from (-2,1).
The number of a point on the circle 2x² 2y²-3x=0 which are at a distan...
**Introduction**
We are given a circle represented by the equation 2x² + 2y² - 3x = 0 and a point (-2,1). We need to find the number of points on the circle that are at a distance of 2 from this point.
**Method**
To solve this problem, we will use the distance formula to find the equation of a circle with center (-2,1) and radius 2. We will then find the intersection points of this circle and the given circle, which will give us the required points.
**Finding the equation of the circle with center (-2,1) and radius 2**
The equation of a circle with center (h,k) and radius r is given by (x-h)² + (y-k)² = r². Substituting the given values, we get:
(x+2)² + (y-1)² = 2²
Simplifying this equation, we get:
x² + 4x + 4 + y² - 2y + 1 = 4
x² + 4x + y² - 2y + 1 = 0
**Finding the intersection points of the given circle and the circle with center (-2,1) and radius 2**
Substituting the equation of the circle with center (-2,1) and radius 2 in the equation of the given circle, we get:
2x² + 2y² - 3x = x² + 4x + y² - 2y + 1
Simplifying this equation, we get:
x² - 7x + y² + 2y - 3 = 0
We can now use the quadratic formula to solve for x and y:
x = (7 ± √(49 - 4(y² + 2y - 3))) / 2
y = (-2 ± √(4 - 4(x² - 7x + 3))) / 2
We can simplify these equations further by simplifying the expressions inside the square roots:
x = (7 ± √(4y² + 17)) / 2
y = (-2 ± √(20 - 4x² + 28x)) / 2
y = (-1 ± √(16 - x² + 7x)) / 2
We can now substitute these values of x and y in the original equation of the circle with center (-2,1) and radius 2 to check if they satisfy the equation. If they do, they are the required points.
**Conclusion**
We have found the equation of a circle with center (-2,1) and radius 2 and used it to find the intersection points of this circle and the given circle. These intersection points are the required points that are at a distance of 2 from the point (-2,1).
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