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When a cone is cut by a plane, its intersection line may be? A) Ellipse B) Circle C) Rectangle D) Isosceles triangle
If it is a horizontal plane, it is a circle
If it is a vertical plane cut from the center, it is a triangle
Use a plane to cut a sphere, what line is the intersection line, and what plane figure does the intersection line form
That's called the intersection line. It's a circle that forms a circular plane
Section plane is called section line?
The intersection of a section plane and a solid surface
How many points of intersection of parabola y = - 3x2 + 2x-1 image and coordinate axis?
One
Intersection with abscissa: make - 3x ^ 2 + 2x-1 = 0, B ^ 2-4ac
When AB is the same sign, the symmetry axis of the parabola is on the left side of the y-axis?
A parabola with an opening up or down
Axis of symmetry x = - B / 2A
So when AB is the same sign, x0, opening up, a
How much is 50 degrees 29 minutes - 39 degrees 31 minutes~~~~~~~~~~~~~~~~~~~
Speed Smecta
50 degrees 29 minutes - 39 degrees 31 minutes
=49 degrees 89 - 39 degrees 31
=10 degrees 58 minutes
If a = the square of a + the square of 5B - 4AB + 2B + 100, when we find the value of a and B, the formula A has the minimum value
If x + 1 / x = 4, then x & # 178; + X & # 178; 1 / x =?
X + 1 / x = 4,
X & # 178; + X & # 178; 1 / 2
=X & # 178; + 2 + X & # 178; 1 / 2 - 2
=(x + x 1 / 2) ^ 2-2
=4^2-2
=14
How to solve the binary quadratic equations?
x^2+y^2=52
xy=24
Two equations can be obtained simultaneously: (X-Y) ^ 2 = 4
X = y + 2 or Y-2
Back to the second equation
When x = 2 + y
y^2+2y-24=0
Y = 4 or - 6
x=6,y=4
Or x = - 4, y = - 6
When x = Y-2
Y = 6 or - 4
y=6,x=4
Or y = - 4, x = - 6
A certain work is completed by Party A alone for 3 hours, and by Party B alone for 4 hours. After Party B alone for 1 hour, Party A and Party B work together to complete the rest of the work. This work is completed in () hours
A. 79B. 67C. 167D. 157
Suppose that after Party B has worked alone for one hour, Party A and Party B can work together for X hours, and the total workload is set as unit 1, then the equation can be obtained: 14 + (13 + & nbsp; 14) & nbsp; X = 1, and the solution is: X = 97 (hours), so the total working time is (97 + 1) = 167 hours, so C
RELATED INFORMATIONS
- 1. Find the plane that passes through the origin and intersects with the conical surface as a circle
- 2. How to find the intersection of two planes
- 3. If two intersecting planes are perpendicular to the third plane at the same time, then the intersection line of the two intersecting planes is perpendicular to the third plane. Can this be used as a judgment theorem? High school textbooks don't have this theorem, so we need to write a lot when proving it! But if two intersecting planes are perpendicular to the third plane at the same time, their intersection line should also be perpendicular to the third plane. Can we judge it directly as a theorem?
- 4. Find the curve integral I = ∫ Γ z2ds, where Γ is the curve x2 + Y2 + Z2 = 4, x + y + Z = 0
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- 8. Known equation x2 + y2-2 (T + 3) x + 2 (1-4t2) y + 16t4 + 9 = 0 When t is the value, the radius of the equation is the largest
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- 12. A cone is a plane and a surface?
- 13. Is the surface of a cylinder or cone a plane or a curved surface?
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- 16. Are univalent hyperbolas and bivalent hyperbolas formed by the rotation of hyperbolas on which axis?
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- 19. The plane α. β. γ intersects each other, and the intersection line is ABC. A ‖ B
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