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The image of a certain function passes through the point (- 1,2), and the value of function y decreases with the increase of independent variable x. please write a function relation that meets the above conditions___ .
∵ y decreases with the increase of X, ∵ K ＜ 0. And ∵ a straight line crosses a point (- 1,2), ∵ the analytic formula is y = - 2x or y = - x + 1, etc. so the answer is: y = - 2x (the answer is not unique)
It is known that F1F2 is the two focal points of the ellipse x ^ 2 / 4 + y ^ 2 = 1, and P is the point on the ellipse
Find the minimum value of absolute value Pf1 * absolute value PF2,
Find the minimum product of absolute value Pf1 and absolute value PF2,
First of all, e = the distance between the inverted left (right) focus of a point on the ellipse / the distance from this point to the left (right) guide line (this is the formula of focal radius). So you set P (x, y) so: absolute value Pf1 = a + ex, absolute value PF2 = a-ex, set M = absolute value Pf1 * absolute value PF2, then M = (a + Ex) (...)
One
As for the inverse scale function, if the independent variable x is expanded by K times, the function y is reduced by K times
What's wrong with this sentence? Is it a mistake of expression or itself
A function of the form y = K / X (k is constant and K ≠ 0) is called an inverse proportional function
I think the mistake of this sentence lies in the use of words. Instead of expanding and narrowing, it should be said
If the independent variable x becomes K times, then y becomes 1 / K
The inverse proportional function y = K / x, when k is constant, if the independent variable x expands by K times, the function y decreases by K times
K cannot be 0
Thank you for your adoption
Find that F1F2 is the left and right focus of y = 1 (0 is less than B is less than 1) of the ellipse e: X,
The line L passing through F1 intersects with e at two points a and B, and the absolute values of af2, AB and BF2 form an arithmetic sequence. The first question: the absolute value of ab. the second question: if the slope of the line L is 1, find the value of B
The even function f (x) is defined on R and is monotone increasing function on the interval [0, + ∞), such as f (lgx) > F (1). The range of X is obtained
Because f (x) is an even function and increases at [0, + ∞), f (x) decreases at (- ∞, 0]
In addition, f (1) = f (- 1)
F (lgx) > F (1), lgx > 1, x > 10 on [0, + ∞), and lgx on (- ∞, 0]
The two focal points of the ellipse F1F2 are on the x-axis. The circle with diameter of | F1F2 | and the ellipse have a point of intersection (3,4). Find the standard equation of the ellipse!
Please give the process
The monotone increasing interval of square + 1 of function y = x is
This function is the function y = x square translation (0,1)
According to the image, the monotone increasing interval is (0, positive infinity)
0 to positive infinity
Please give me a complete definition of Quasilinear of ellipse and hyperbola, and make a good map
Can I remember without death? X = + - A ^ 2 / C I need to understand, especially hyperbola
The ratio of the distance from any point on the ellipse / hyperbola to a focal point and its corresponding quasilinear is eccentricity. Ellipse: according to the first definition, the sum of the distances from a point on the ellipse to two focal points is 2A
Monotone interval of square + X + 2 of function y = x
In y = x ^ 2 + X + 2
The axis of symmetry is a straight line x = - 1 / 2
Because a = 1 > 0, the image is up
So the monotone decreasing interval is (negative infinity, - 1 / 2]
Monotone increasing interval is [- 1 / 2, positive infinity)
y=x^2+x+2 ,y'=2x+1, y'=0,x=-1/2
X0 increment
x> - 1 / 2 monotone increasing x
What is the hyperbolic and quasi curve in high school mathematics
Refer to the second definition of E: the ratio of the distance from the point on the curve to the focus and the distance to the guide line
x=±a²/c
Do you have an ellipse
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