![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
What is the area of the triangle f2ab if a straight line passes through the left focus F1 of the ellipse x ^ 2 / 25 + y ^ 2 / 16 = 1 and the line parallel to the Y axis intersects the ellipse and ab? There is another problem: the two foci F1F2 of the ellipse x ^ 2 / 25 + y ^ 2 / 16 = 1, P is the point on the ellipse, if the triangle f1pf2 is a right triangle (angle f1pf2 = 90 degrees), find the area of the triangle f1pf2
1) ∵ a = 5, B = 4 ∵ C = 3 2C = 6 AF1 + af2 = 2A = 10 af2 = 10-af1 ∵ af1f2 is a right triangle ∵ af2 & # 178; = AF1 & # 178; + (2C) &# 178; = > 100-20af1 + AF1 & # 178; = AF1 & # 178; + 36 = > AF1 = 3.2 = > AB = 2af1 = 6.4
Let F1 and F2 be the two focal points of the ellipse X225 + y216 = 1, and the intersection ellipse of the straight line passing through F1 and parallel to the y-axis is at two points a and B, then the area of △ f2ab is ()
A. 245B. 485C. 965D. 1925
From the elliptic equation X225 + y216 = 1, a = 5, B = 4, then C = 3, let F1 be the left focus, then F1 (- 3, 0), so the intersection ellipse of straight line passing through F1 and parallel to y axis is (- 3165), (3, - 165), then | ab | = 325, and F1F2 = 6, so the area of △ f2ab s = 12 × | ab | × F1F2 = 965, so choose: C
F1, F2 are the two focal points of the ellipse X29 + Y27 = 1, a is the point on the ellipse, and ∠ af1f2 = 45 °, then the area of △ af1f2 is___ ．
From the meaning of the title, we can get the conclusion The equation of the ellipse is X29 + Y27 = 1, a = 3, B = 7, and C = A2-B2 = 2, so the focal length | F1F2 | = 22, \| according to the definition of the ellipse, the equation of the ellipse is X29 + Y27 = 1, \| y227 = 1, a = 3, B = 7, which can get C = A2-B2 = 2, so the focal length | F1F2 | F2 | f | f | F2 | 12 | f | 2 | 2 | 2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-2-1 - | AF1 |) 2 = | AF1 | 2-4 | AF1 | + 8, the solution is | AF1 | = 72, so the area of △ af1f2 is s = 12 | AF1 | · | F1F2 | = 12 × 72 × 22 ×22=72．
F1 and F2 are the two focal points of the ellipse x ^ 2 / 2 + y ^ 2 = 1, a is a point on the ellipse, and ∠ af1f2 = 45 °, then the area of △ af1f2 is
A ^ 2 = 2, C = 1, B = 1. When ∠ af1f2 = 45 °, point a is at the end of the minor axis, s △ af1f2 = 2 * 1 / 2 = 1
999 and 6 / 7 + 99 have 6 / 7 + 9 and 6 / 7 + 6 / 7 = please write the formula
(999+99+9+1)*(6/7)=1108
The combination of 5 0.2 with operation symbols is equal to 0.1.2.3 respectively
(0.2－0.2)÷0.2×0.2×0.2＝0
（0.2＋0.2）÷0.2－0.2÷0.2＝1
（0.2＋0.2）÷0.2－（0.2－0.2）＝2
（0.2＋0.2）÷0.2＋0.2÷0.2＝3
In order to strengthen citizens' awareness of water saving and make rational use of water resources, a city adopts price regulation. If the price of tap water in the city is 9.5 cubic meters, it should be charged
The unit price of the part with monthly water consumption y less than or equal to 6 cubic meters is 2 yuan per cubic meter
Monthly water consumption of 6 cubic meters less than or equal to 10 cubic meters, the unit price is 4 yuan per cubic meter
The unit price of the part with water consumption of more than 10 cubic meters per month is 8 yuan per cubic meter
Q1: if it is known that the household consumed 14 cubic meters of water in February, it should be charged RMB
2: It is known that the water fee paid by the household in March is 44 yuan. If the household uses X cubic meters of water (x is greater than 10) in March, calculate the value of X
3. If the household uses 20 cubic meters of water in April and may (more in May than in June) and pays a total water fee of 64 yuan, how many cubic meters of water will the household use in April and may?
Please use the equation solution!
Question 1: 6 × 2 + 4 × 4 + 8 × 4 = 60 yuan
Question 2: suppose the water consumption in March is x cubic meters, then
Y = 8 (X-10) + 6 × 2 + 4 × 4 = 44, x = 12 (M3)
Question 3: suppose the water consumption in April is x cubic meters, then the water consumption in May is (20-x) cubic meters, because the water consumption in May is more than that in April
Eleven out of thirteen (four out of five times three is twenty-six out of three) is a simple calculation
Multiplicative distributive law
My composition about listening to music is about 150 words
I love music. Music is the real world language. Regardless of race, religion, gender and age, human beings can understand music and get the feeling of touching body and mind from music. I love music. In music, we can feel the ultimate harmony that sound can achieve. This is a kind of beauty with great rhythm, which is
Mathematics 3-13 question 17, 24 question 5-13 question 38, 39 question 7-13 third big question 1 small question
3-13 question 24 is 6
5-13 questions 39 and 610
7-13 third question 1 sub question (4x2x3.14 + 5x2x3.14 + 3x2x3.14) / 4 = 18.84 (CM)
I don't know anything else
RELATED INFORMATIONS
- 1. F1, F2 are the two focal points of the ellipse X29 + Y27 = 1, a is the point on the ellipse, and ∠ af1f2 = 45 °, then the area of △ af1f2 is___ ．
- 2. The midpoint problem of conic chord To solve the linear equation of the chord of hyperbola with a (m, n) as the midpoint, we can use f (x1) - f (x2) to get the result. But why does it not exist?
- 3. How to find the locus of the middle point of a line segment whose distance between two points on a conic curve is fixed Take the parabola as an example: Y & # 178; = 2px, (P > 0), a and B are two points on the parabola, and ab = 3, find the trajectory equation of the midpoint m in ab
- 4. The relationship between the slope of focus chord and the ratio of focus chord and eccentricity of conic curve? RT
- 5. Given that a, B, C are real numbers, f (x) = AX2 + BX + C, G (x) = ax + B, when - 1 ≤ x ≤ 1 | f (x) | ≤ 1. (1) prove: | C | ≤ 1; (2) prove: when - 1 ≤ x ≤ 1, | g (x) | ≤ 2; (3) let a > 0, when - 1 ≤ x ≤ 1, the maximum value of G (x) is 2, and find f (x)
- 6. F (x) = log2 [(1-ax) / (x-1)] odd function a is a constant. 1. Find the value of A. 2. Prove that f (x) monotonically decreases in the interval (1, positive infinity), 3.3. If the inequality f (x) B - (1 / 2) ^ x holds for any value of X on [3,5], find the value range of real number B
- 7. How to judge whether a function is even or odd
- 8. What is "odd function. Even function"? We don't have that in our math books, But there are some problems about odd function and even function Please be more specific
- 9. Given that f (x) is an even function, G (x) is an odd function, f (x) + G (x) = x ^ 2 + 2 ^ x, find f (1)
- 10. Let f (x) be a continuous even function on (- ∞, + ∞), and prove that f (x) = ∫ (0 → x) f (T) DT is an odd function
- 11. The line L passing through the focus f on the ellipse 2x ^ 2 + y ^ 2 = 2 intersects the ellipse at two points a and B to find the maximum area of Δ AOB (o is the origin) The answer is only √ 2 / 2. Is there anything wrong in it? Or is the answer wrong There's a wrong step in the middle. Oh, forget it
- 12. If the line y = KX intersects the ellipse x ^ 2 / 4 + y ^ 2 = 1 at two points a and B, and ab ≥ √ 10, find the value range of K
- 13. As shown in the figure, the straight line y = kx-1 intersects the x-axis and y-axis at two points B and C respectively, Tan ∠ OCB = 12 (1) Find the coordinates of point B and the value of K; (2) if point a (x, y) is a moving point on the line y = kx-1 in the first quadrant, try to write out the functional relationship between the area s of △ AOB and X when point a moves; (3) explore: under the condition of (2): ① when point a moves to what position, the area of △ AOB is 14; ② if it holds, whether there is a point P on the X axis So that △ POA is an isosceles triangle? If it exists, please write the coordinates of all P points that meet the condition; if not, please explain the reason
- 14. In the plane rectangular coordinate system, the coordinates of point a are (3, - 4), its symmetry about y axis, the coordinates of point B are (), △ OAB are () triangles
- 15. In the plane rectangular coordinate system, B and a are on the X and Y axes respectively, and the coordinate of B is (3,0) ∠ ABO = 30 degree AC bisection ∠ OAB intersects X axis at C (1) Find the coordinates of point C (2) If D is the middle point of AB, ∠ EDF = 60 °, (E on AC, f on BC), it is proved that CE + CF = OC
- 16. 11. It is known that y + 1 is proportional to x, and when x = 3, y = 5, the functional relationship between Y and X is obtained, and the value of a when the point (a, - 2) is on the function image is obtained
- 17. Given the function y = x + 2 (1) when x takes what value, the value of Y is - 5?; (2) when x takes what value, the value of function is positive?; (3) find the function image and X
- 18. It is proved that f (x) is integrable and odd on [- A, a], then ∫ f (x) DX = 0
- 19. It is proved that f (x) = 1 / 2 + 1 / 2 is a product function It is proved that f (x) = 1 / 2 + 1 / 2 is a product function
- 20. F (x) is integrable in [a, b], integral upper limit function Φ (x) is continuous, why, how to prove?