Let the ellipse with the center at the origin and the hyperbola 2x2-2y2 = 1 have a common focus, and their eccentricities are reciprocal to each other, then the equation of the ellipse is______

Let the ellipse with the center at the origin and the hyperbola 2x2-2y2 = 1 have a common focus, and their eccentricities are reciprocal to each other, then the equation of the ellipse is______

In hyperbola, a = 12 = B, f (± 1,0), e = CA = 2. The focus of ellipse is (± 1,0), and the eccentricity is 22. Then the length of major axis is 2 and the length of minor axis is 1. The equation is X22 + y2 = 1. So the answer is: X22 + y2 = 1
The difference formula of A1, A2 is known
If the known tolerance is not zero, the arithmetic sequence an satisfies a 2 = 3, and a 1, a 3 and a 7 are proportional
(1) Formula for finding the general term of an
(2) The sequence BN satisfies: BN = [(an / an + 1) + (an + 1 / an)], find the first n terms and Sn of the sequence BN
(1) Let {an} tolerance be D, D ≠ 0 ∵ A2 = 3, and A1, A3, and A7 be equal proportion sequence {a1 + D = 3} {(a1 + 2D) & # 178; = A1 (a1 + 6D) ② = = > 4a1d + 4D & # 178; = 6a1d = = > a1d = 2D, ∵ D ≠ 0 ∵ A1 = 2, d = 1 ∵ an = n + 1 (2) BN = (n + 1) / (n + 2) + (n + 2) / (n + 1) = [(n + 2) - 1] / (n + 2) + [(n + 1] / (n + 1) / (n + 2) / (n + 1) = [(n + 1) / (n + 1) / (n + 2) / (n + 1) / (n + 1) / (n + 1) / (
Solution 1, A3 / A1 = A7 / A3
When D is greater than zero, A1 = 2D, A2 = 3, A1 = 2, d = 1, an = n + 1
When D is less than zero, it does not meet the equal ratio condition
Two
Seeking four operations in grade six of primary school
The more the better! It's better not to be a Mathematical Olympiad problem, but it's more complicated The more questions, the more additional points
1. 3/7 × 49/9 - 4/3 2. 8/9 × 15/36 + 1/27 3. 12× 5/6 – 2/9 ×3 4. 8× 5/4 + 1/4 5. 6÷ 3/8 – 3/8 ÷6 6. 4/7 × 5/9 + 3/7 × 5/9 7. 5/2 -（ 3/2 + 4/5 ） 8. 7/8 + （ 1/8 + 1/9 ） 9. 9 × 5/6 + 5/6 ...
Elementary school fifth grade mathematics volume two oral arithmetic questions with answers
Urgent! Need to use it urgently! Hurry up! It's better to do oral arithmetic in Volume 2 of fifth grade, 50 courses, and ask for answers! Everyone, help!
At the same time, a 1500 meter tunnel is opened together. The first engineering team starts to dig 14 meters at one end every day. The second engineering team starts to dig 16 meters at the other end every day. How many days later can the tunnel be dug through? 14. A and B work together to write a 7000 word manuscript at the same time
In △ ABC, ab · AC = 1, ab · BC = − 3. (1) find the length of AB edge; (2) find the value of sin (a − b) sinc
(1) ∵ ab · AC = ab · (AB + BC) = ab · AB + ab · BC = ab2-3 = 1. That is to say, the length of AB side is 2. (5 points) (2) from the known and (1) are: 2bcosa = 1, 2acos (π - b) = - 3, ∵ acosb = 3bcosa (8 points) from the sine theorem: sinacosb = 3sinbcosa (10 points) ∵ sin (?)
In the arithmetic sequence {an} with non-zero tolerance, A1 = 2, and A1, A3, a7 are equal proportion sequence. (1) the general term formula of the sequence {an}
(2) If the sum of the first n terms of the sequence {BN} is Sn and nanbn = 1, we prove: SN
（1）an=n+1
(2)b[n]=1/n-1/(1+n)
s[n]=1-1/(1+n)
Four operations 200 questions (primary school) grade 6
Add mixed eg XX + XX × XX △ XX
How to do the thinking problem on page 47 of mathematics in Volume 2 of grade 4?
Hurry!
It's very easy to double both sides of the fourth formula, and you will find that the problem is too easy
▲=150.□=100,○=75
There are no books. You should post the title next time
I think it's better than asking
come on.
In the triangle ABC, a, B and C are the opposite sides of a.b.c. the vector M = (a, b) and the vector n = (B, c)
If the vector m is parallel to the vector n, find the value of angle B satisfying root three SINB + CoSb root three = 0. If the vector m · vector n = 2B ^ 2 and a-c = π / 3, find the value of CoSb.
If B = π / 2, then a ^ 2 + C ^ 2 = B ^ 2 = AC / 3 or 2 π / 3, then a ^ 2 + C ^ 2 = B ^ 2 = AC and a ^ 2 + C ^ 2 ≥ 2Ac
It is known that {an} is an arithmetic sequence with non-zero tolerance, A3 = 5, and A1, A2, A5 are equal proportion sequence. (1) find the general term formula of {an}; (2) find the first n term and Sn of {2 ^ an}
Let the difference in the arithmetic sequence be D, then A1 = 5-2d; A2 = 5-D; A5 = 5 + 2D, and because A1, A2, A5 are equal ratio sequence, so A2 / A1 = A5 / A2, substitute the above formula to get D1 = 2, D2 = 0 (it should be known that {an} is the arithmetic sequence with non-zero tolerance, so rounding off) the general term formula is an = a1 + (n-1) d = 2N-1
(a2)^2=(a1)*(a5)
(a3-d)^2=(a3-2d)(a3+2d)
(5-d)^2=(5-2d)(5+2d)
25-10d+d^2=25-4d^2
3d^2-10d=0
d(3d-10=0
D = 0 (exclusion) d = 10 / 3
a1=a3-2d=5-2*10/3=-5/3
an=(n-1)10/3-5\3
q=2^an/2^2n-1=2^an-(an-1)=2^(n-1)10/3-5/3-(n-2)10/3+5/3=2^10/3
a1=2^a1=2^(-5/3)
sn=2^(-5/3)(1-(2^10/3)^n）/(1-2^10/3)
(a3-d)^2=(a3-2d)(a3+2d)
Think about it for yourself. I went to sleep. I was too sleepy
a2)^2=(a1)*(a5)
(a3-d)^2=(a3-2d)(a3+2d)
(5-d)^2=(5-2d)(5+2d)
25-10d+d^2=25-4d^2
3d^2-10d=0
d(3d-10=0
D = 0 (exclusion) d = 10 / 3
a1=a3-2d=5-2*10/3=-5/3
an=(n-1)10/3-5\3
Q = 2 ^ an / 2 ^... Expansion
a2)^2=(a1)*(a5)
(a3-d)^2=(a3-2d)(a3+2d)
(5-d)^2=(5-2d)(5+2d)
25-10d+d^2=25-4d^2
3d^2-10d=0
d(3d-10=0
D = 0 (exclusion) d = 10 / 3
a1=a3-2d=5-2*10/3=-5/3
an=(n-1)10/3-5\3
q=2^an/2^2n-1=2^an-(an-1)=2^(n-1)10/3-5/3-(n-2)10/3+5/3=2^10/3
a1=2^a1=2^(-5/3)
sn=2^(-5/3)(1-(2^10/3)^n）/(1-2^10/3)
Help the low-level ones. Put them away