We know two unascertained Sina and cosa, a ∈ (0, π) for the equation 2x & sup2; - (radical 3 + 1) + M = 0 ① Finding the value of M

We know two unascertained Sina and cosa, a ∈ (0, π) for the equation 2x & sup2; - (radical 3 + 1) + M = 0 ① Finding the value of M

x1^2+x2^2=sina)^2+cosa)^2=1
X1 ^ 2 + x2 ^ 2 = 1 = (x1 + x2) ^ 2-2x1x2 = - (radical 3 + 1) ^ 2-2 * m / 2 = 4 + 2 radical 3-m = 1
M = 3 + 2 radical 3
In the plane rectangular coordinate system, the coordinates of a, B and C are a (5,0), B (0,3) and C (5,3), respectively. O is the origin of the coordinates, and point E is on the line BC. If △ AEO is an isosceles triangle, the coordinates of point E can be obtained. (draw the image, no need to write the calculation process.)
The graph is as follows: (1) if isosceles △ AEO takes a as vertex, then E (1,3); (2) if isosceles △ AEO takes e as vertex, then E (2.5,3); (3) if isosceles △ AEO takes O as vertex, then E (4,3)
If the tolerance of the arithmetic sequence {an} is not zero, the first term A1 = 1, and A2 is the equal proportion middle term of A1 and A5, then the sum of the first 10 terms of the sequence {an} is ()
A. 90B. 100C. 145D. 190
According to the meaning of the title, (a1 + D) 2 = A1 (a1 + 4D), that is, A12 + 2a1d + D2 = A12 + 4a1d, ｜ d = 2A1 = 2. ｜ S10 = 10A1 + 10 × 92d = 10 + 90 = 100
In the plane rectangular coordinate system, three points a (0,1), B (2,0), C (2,1.5) are known. Point O is the origin
(1) Find the area of △ ABC (solved)
(2) If there is a point P (a, & frac12;) in the second quadrant, the area of the quadrilateral abop is expressed by the formula containing a;
(3) Under the condition of (2), is there a point P that makes the area of the quadrilateral abop equal? If so, find out the coordinates of point p; if not, explain the reason
1L is not wrong, not wrong! How did Khan dada say that I was wrong-
2) The value range of a should be discussed, and then the area can be calculated by integral method,
3) It seems that the title is really wrong. How much is it equal to? There are no conditions
Are you sure the title is correct
Are you sure the title is correct
If the tolerance of the arithmetic sequence {an} is not zero, the first term A1 = 1, and A2 is the equal proportion middle term of A1 and A5, then the sum of the first 10 terms of the sequence {an} is ()
A. 90B. 100C. 145D. 190
According to the meaning of the title, (a1 + D) 2 = A1 (a1 + 4D), that is, A12 + 2a1d + D2 = A12 + 4a1d, ｜ d = 2A1 = 2. ｜ S10 = 10A1 + 10 × 92d = 10 + 90 = 100
In the plane rectangular coordinate system, take the origin o as the center of the circle and 5 as the radius as the center of the circle. The coordinates of a, B, C and three points are
The three coordinates are (3,4) (- 3, - 3) (4, - root 10)
Try to judge the position relationship between a, B, C and the center o
Calculate the distance from a, B and C to the center of the circle (i.e. the origin)
|OA | = under the root sign (3 ^ 2 + 4 ^ 2) = 5, on the circle
|OB | = under root sign (3 ^ 2 + 3 ^ 2) = root sign 185, outside the circle
A is tangent to the circle B is inside the circle C is outside the circle
The sum of the two series is not equal to the sum of the two series
Let the tolerance DA2 = a1 + Da4 = a1 + 3da10 = a1 + 9ds10 = (a1 + A10) * 10 / 2 = 5 (2A1 + 9D) = 1102a1 + 9D = 22a1. A2. A4 be the equal ratio sequence A2 * A2 = A1 * A4 (a1 + D) ^ 2 = A1 (a1 + 3D) d ^ 2 - A1 * d = 0d = A1 (d = 0 rounding off) 2 * a1 + 9 * A1
In the plane rectangular coordinate system, the coordinates of a, B and C are a (5,0), B (0,3) and C (5,3), respectively. O is the origin of the coordinates, and point E is on the line BC. If △ AEO is an isosceles triangle, the coordinates of point E can be obtained. (draw the image, no need to write the calculation process.)
The graph is as follows: (1) if isosceles △ AEO takes a as vertex, then E (1,3); (2) if isosceles △ AEO takes e as vertex, then E (2.5,3); (3) if isosceles △ AEO takes O as vertex, then E (4,3)
It is known that in the arithmetic sequence an, the tolerance D is not equal to 0, and A1, A5 and A17 are equal proportion sequence, then (a1 + A5 + A17) / (A2 + A6 + A18) =?
A5 = a1 + 4D, A17 = a1 + 16d, because A1, A5, A17 are proportional sequence, so (a1 + 4D) ^ 2 = A1 * (a1 + 16d), so (A1) ^ 2 + 8A1 * D + 16d ^ 2 = (A1) ^ 2 + 16a1 * D, that is, 2D ^ 2 = A1 * D, because D ≠ 0, so A1 = 2D, so (a1 + A5 + A17) / (A2 + A6 + A18) = [2D + (2D + 4D) + (2D + 16d)] / [(2D + D) + (2D + 5d) + (2D + 17D] / [(2D + 5d)]
a1*(a1+16d)=(a1+4d)²
a1=2d
Then go back
=26/29
a1*a17=(a5)^2
That is A1 (a1 + 16d) = (a1 + 4D) ^ 2
a1=2d
It can be calculated by substituting the formula
Given that the length of the line segment l passing through point P (2,3) and cut by two parallel lines 3x + 4y-7 = 0 and 3x + 4Y + 8 = 0 is D, 1) find the minimum value of D, 2) what is d
2) when D is, the line L is parallel to the x-axis
The smallest time is when the line L is perpendicular to two parallel lines
d=|-7-8|/5=3
When parallel to the X axis, the D and X axes intercept the same distance
y=0,d=7/3- (-8/3)=5