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The equation of the circle whose center is C (3, - 5) and tangent to the line x-7y + 2 = 0 is______ ．
∵ the distance from the center of a circle to the tangent d = R, that is, r = D = | 3 + 35 + 2 | 12 + 72 = 42, the center of a circle C (3, - 5), the equation of circle C is (x-3) 2 + (y + 5) 2 = 32. So the answer is: (x-3) 2 + (y + 5) 2 = 32
The first problem: known set a = {x | x ＜ - 2 or 3 ＜ x ≤ 4}, B = {x | X & # 178; - 2x-15 ≤ 0}
Find (1) a ∩ B (2) if C = {x | x ≥ a} and B ∩ C = B, find the range of a?
Question 2: Sina, cosa are two real roots of the equation 4x & # 178; - 4mx + 2m-1 = 0, a ∈ (- π / 2,0) to find the value of M and a?
(1){x|-3
Given a = {x | x ＞ 1}, B = {x | X & # 178; - 2x ＜ 0}, then a ∩ B=
B={x|x(x-2)
RELATED INFORMATIONS
- 1. Given that the moving circle is circumtangent to the circle (x + 2) 2 + y2 = 4 and tangent to the straight line x = 2, the trajectory equation of the center P of the moving circle is obtained
- 2. If the line x + y = C is tangent to the circle X & # 178; + Y & # 178; = 2, then C = () 3Q
- 3. Find the tangent equation passing through point a (- 4,3) and tangent to circle (x + 1) square + (y + 1) square = 25 Find the tangent equation passing through point a (- 4,3) and tangent to circle (x + 1) square + (y + 1) square = 25
- 4. Tangent equation of P (- 5, - 2) and circle x ^ 2 + y ^ 2 = 25 RT
- 5. Find the tangent equation of the circle x 2 + y 2 = 4 from point a (2,4)
- 6. A beam of light is emitted from a (- 2,3), reflected by x-axis, and tangent to the circle C (x-3) 2 + (Y-2) 2 = 1. The equation of the straight line of the reflected light is obtained Method 1: the symmetrical point of point a about the x-axis is on the line where the reflected light is located PS: it's a clue to the title, but I'm not good at it
- 7. Find the equation of the circle which passes through the point m (3, - 1) and the circle C: x2 + Y2 + 2x-6y + 5 = 0 and is tangent to the point n (1,2). Why can't we use the equation of the circle system? Isn't there an intersection point between the tangent and the circle?
- 8. It is known that the ellipse takes the symmetry axis as the coordinate axis, and the major axis is three times of the minor axis, and passes through the point (3,0)
- 9. Find the equation of a straight line passing through point a (3,4) and tangent to circle x square + y square = 9 Such as the title
- 10. The equation of the line parallel to the line 2x-y + 1 = 0 and tangent to the circle x2 + y2 = 5 is () A. 2x-y + 5 = 0b. X2-y-5 = 0C. 2x + y + 5 = 0 or 2x + Y-5 = 0d. 2x-y + 5 = 0 or 2x-y-5 = 0
- 11. Given the circle C: X & # 178; + Y & # 178; = 4, the tangent equation of the circle passing through the point (- 2,1) is? What is the answer and the difference between the tangent equation and the ordinary equation?
- 12. (2010` Guangzhou the first mock exam) the known moving circle C passes through point A (-2,0) and is cut in with the circle M: (X-2) ^2+y^2=64. (1) Find the trajectory equation of the center of moving circle C (2) Let L: y = KX + m (where k, m ∈ z) and (1) intersect at two different points B and D, and hyperbola (x ^ 2) / 4 - (y ^ 2) / 12 = 1 intersect at two different points e F. ask if there is a straight line L such that vector DF (vector) + be (vector) = 0 (vector). If there are, please point out how many such lines. If not, please explain the reason
- 13. Let the center of the circle x ^ 2 + y ^ 2-4x + 2y-11 = 0 be a and the point p be on the circle, then the trajectory equation of the midpoint m of PA is
- 14. Ask for help high school "basic inequality" problem: known circle C: the square of X + the square of Y + BX + ay-3 = 0 (a, B are positive real numbers) on any point about the straight line L: 1 Given that any point on the circle C: x square + y square + BX + ay-3 = 0 (a, B are positive real numbers) with respect to the symmetric point of the line L: x + y + 2 = 0 is on the circle C, then the minimum value of 1 / A + 3 / B is___ .
- 15. Given that P is any point of the circle C: x ^ 2 + y ^ 2 + 4x + ay-5 = 0, the symmetric point of P about 2x + Y-1 = 0d is still on the circle
- 16. It is known that the straight line X-Y + 3 = 0 and the circle x + y = 1. Judge their position relation and prove it
- 17. Circle x ^ + y ^ = 1 and circle x ^ + y ^ - 2x-2y = 0, the position relation is? (^ is 2, that is, x square or Y Square) So R + r = 1 + radical 2, but I calculate that the distance between the two center points is = radical 2. Why is it tangent??? The distance between the center of the circle is less than the sum of the radii, so it intersects!!!!!
- 18. Given that the circle m is tangent to the x-axis, the center of the circle is on the straight line x-2y = 0, and the maximum distance from the moving point on the circle m to the y-axis is 3, find the square of the circle M
- 19. Given the curve C: x2 + y2-2x-4y + M = 0. (1) when the value of M is, the curve C represents a circle; (2) if the curve C and the straight line x + 2y-4 = 0 intersect at two points m and N, and OM ⊥ on (o is the origin of the coordinate), find the value of M
- 20. It is known that P (x, y) is a moving point on the circle C: x + y-2y = 0. If x + y + m ≥ 0 is constant, the value range of real number m is obtained