In the space rectangular coordinate system o-xyz, the distance between the point P on the coordinate axis and a (1,1,1) is equal to the root sign 3, so the point P has the same number

In the space rectangular coordinate system o-xyz, the distance between the point P on the coordinate axis and a (1,1,1) is equal to the root sign 3, so the point P has the same number

Four, origin, one point on each of the three axes
The vertex of the known angle α coincides with the origin of the rectangular coordinate system, the starting edge is on the positive half axis of the x-axis, and the final edge passes through the point P (- 1,2). Find (1) sin α, cos α, Tan α (2) sin (α − 5 π) cos (− π 2 − α) cos (8 π − α) sin (α − 3 π 2) sin (− α − 4 π) Tan (α + π)
(1) The vertex of ∵ angle α coincides with the origin of rectangular coordinate system, the starting edge is on the positive half axis of X axis, and the final edge passes through the point P (- 1,2), ∵ op | = 5 ∵ sin α = 255, cos α = - 55, Tan α = - 2 (2) primitive = sin (α − 5 π) cos (− π 2 − α) cos (8 π − α) sin (α − 3 π 2) sin (− α − 4 π) Tan (α + π) = cos α = 55
The vertex of the known angle α coincides with the origin of the rectangular coordinate system, the starting edge is on the positive half axis of the x-axis, and the final edge passes through the point P (- 1,2). The value of sin (2 α + 9 π 4) + Tan (2 α − π) is calculated
According to the meaning and P (- 1,2), we get Tan α = - 2, sin α = 255, cos α = - 55, ∩ sin2 α = 2Sin α, cos α = - 45, Cos2 α = Cos2 α - sin2 α = - 35, tan2 α = 43, then sin (2 α + 9 π 4) + Tan (2 α − π) = sin (2 α + π 4) + tan2 α = 22 (sin2 α + Cos2 α) + tan2 α = 22 (- 45-35) + 43 = 43 − 7210
In the arithmetic sequence {an}, A1 = 1, A2 = 3, an + 2 = 3an + 1-2an (n belongs to N +), it is proved that the sequence {an + 1-an} is an arithmetic sequence
a(n+2)-an=2(an-a(n-1))
a2-a1=3-1=2
The sequence {an + 1-an} is a sequence whose first term is 2 and whose common ratio is 2
(56-x) the square of the quotient divided by 4 minus the square of the quotient divided by 4 equals 100?
[(56-x)/4]^2-[(x/4)^2]=100
At the same time, the equation * 4 ^ 2 is obtained
(56-x)^2-x^2=1600
Open square term
x=1536/112=96/7=13.7
Given that the empty set is a subset of {x | x2-x + a = 0}, then the value range of real number a is?
What's the difference between a subset and a proper subset?
An empty set is a subset of any set
So here a is any real number
If it's a proper subset
Then the collection has at least one element
So the discriminant = 1-4a > = 0
A
The monotone decreasing function f (x) defined in (- ∞, 3) satisfies that f (a ^ 2-sinx) ≤ f (a + 1 + cos ^ 2x) has a solution, and the range of a is obtained
Because the function domain is (- ∞, 3) and monotonically decreasing, 3 > A ^ 2-sin (x) > = a + 1 + cos (x) ^ 2 holds for all x, 3 > A ^ 2-sin (x) holds for all x, and the solution - √ 2 = 0 holds for all X. let y = sin (x), that is, the inequality y ^ 2-y + A ^ 2-a-2 > = 0 holds on [- 1,1]
In the arithmetic sequence {an}, A1 = 1, A2 = 3, an + 2 = 3an + 1-2an (n belongs to N +)
II write input n (n > = 3) value, output A1, A2 And draw the program block diagram of the algorithm
II according to (II) algorithm and block diagram, write an input n value, output A1, A2 The computer program of an value
I'm really disappointed that no one can make such a big Baidu
Calculate the expression of an
An-a (n-1) = 4 is obtained by means of cumulative multiplication, so when n ≥ 2, an is an arithmetic sequence, an = 4n-3
When n = 1, it conforms to the above formula, so an is an arithmetic sequence, an = 4n-3
After that, it's easy
eldest brother! Have you made any mistakes! An + 2 = 3an + 1-2an is wrong! I think the 3an + 1 on the right should be 3A (n + 1), otherwise you will divide it into 2 = 1, so the 2An may be wrong! Otherwise, if you take n as 1, then 1 + 2 = 3 + 1-2 is divided into 3 = 2, so you should write the title right first!
The square of x minus x equals 56
x^2-x=56
x^2-x-56=0
(x-8)(x+7)=0
x1=8 x2=-7
The empty set is the proper subset of {x | x ^ 2-x + a = 0}, and the value range of the real number a
An empty set is a proper subset of {x | x ^ 2-x + a = 0}, which indicates that {x | x ^ 2-x + a = 0} is not an empty set, so the equation has a solution, so the discriminant is 0,
That is 1-4a "0, a" 1 / 4
An empty set is a proper subset of {x | x ^ 2-x + a = 0}. It shows that the discriminant of root is not less than 0, that is, 1-4a ≥ 0, so a ≤ 1 / 4
Because an empty set is a proper subset of {x | x ^ 2-x + a = 0},
So x has to have a solution, i.e. △ = B & # 178; - 4ac = (- 1) &# 178; - 4A ≥ 0
Find out the value range of A
a≤1/4