The points P (a, - 2), q (2, b), PQ are parallel to the x-axis. Find the values of a and B

The points P (a, - 2), q (2, b), PQ are parallel to the x-axis. Find the values of a and B

a=0,b=-2

Find the maximum value of the period sum of the following functions, and the minimum value is y = sin (x - ly / 3) cosx

y=sin(x-Л/3)cosx
=1 / 2 * SiNx * cosx radical 3 / 2 * cosx * cosx
=1 / 4sin2x radical 3 / 4cos2x radical 3 / 4
=1 / 2Sin (2x - ly / 3) - radical 3 / 4
Period
Maximum 1 / 2-radical 3 / 4
Minimum - 1 / 2 - radical 3 / 4

The equation of a straight line passing through point (3,1) with equal intercept on two coordinate axes is

The intercept is equal on two axes
So we can set the intercept formula: X / A + Y / a = 1
Substituting (3,1) into 3 / A + 1 / a = 1
4/a=1
a=4
So the linear equation is x / 4 + Y / 4 = 1

Is there a simple method for 39 ^ 2-41 ^ 2

39^2-41^2
Using the square difference formula
=（39-41）×（39+41）
= -2×80
= -160

The straight line y = 2X-4 intersects the x-axis and y-axis at two points a and B respectively. O is the circle point. C and D are the symmetrical points of a and B about the origin respectively
(1) Finding the function analytic expression of straight line CD
(2) Area of quadrilateral ABCD

Let x = 0, y = - 4, y = 0, x = 2, so intersection a (2,0) with X axis and intersection B (0, - 4) with y axis
So C (- 2,0) d (0,4)
Let y = ax + B - 2A + B = 0
b=0
The analytic formula is y = 2x + 4
S = ax × by × half × 4 = 2 × 4 × half × 4 = 16

Given that the image of function f (x) = x ^ 2 / (x + m) passes through (4,8), in the sequence {an}, if A1 = 1, Sn is the sum of the first n terms of the sequence {an}, an = f (SN) (n ≥ 2), it is proved that the sequence {1 / Sn} is an arithmetic sequence, and the general term of the sequence {an} is obtained

F (4) = 16 / (4 + m) = 8m = - 2An = Sn & sup2; / (sn-2) SN-S (n-1) = Sn & sup2; / (sn-2) Sn & sup2; - 2Sn SNS (n-1) + 2S (n-1) = Sn & sup2; 2S (n-1) - 2Sn = SNS (n-1) two sides divided by 2SNS (n-1) 1 / sn-1 / S (n-1) = 1 / 2, so 1 / sn-1 / S (n-1) = 1 / 2D = 1 / 21 / S1 = 1 / A1 = 1

There is an electric field in vacuum, and a point charge with positive 5.0 times 10 and negative ninth power C is placed at a certain point in the electric field. The electric field force it receives is 3.0 times 10 and negative fourth power n. the direction is eastward. Find the magnitude and direction of the electric field strength at this point

From the negative ninth power C with Q of 5.0 times 10, f = Eq. so e = f / Q, then we get the fourth power n / C with e of 6.0 times 10. Because it is a positive charge, the direction is from west to East

Given proposition p: ∃ x ∈ R, X2 + 2aX + a ≤ 0. If proposition p is a false proposition, then the value range of real number a is ()
A. （0，1）B. （-∞，0）∪（1，+∞）C. [0，1]D. （-∞，0）∪[1，+∞）

∀ proposition p is a false proposition, ￢ proposition ￢ P is a true proposition, that is, ∀ x ∈ R, X2 + 2aX + a ＞ 0 is tenable, that is, △ = 4a2-4a ＜ 0, the solution is 0 ＜ a ＜ 1, so: a

Fill - 1, 2, - 3, 4, - 5, 6, - 7, 8 and - 9 in the nine palace, so that the product of the three numbers is negative and the sum of absolute values is equal

2 -9 4
-7 -5 -3
6 -1 8

Let f (x) be an original function of function SiNx, then f (x) DX is integrated=

f(x)=∫sinxdx=-cosx+C1
∴∫f(x)dx=∫(-cosx+C1)dx
=-sinx+C1x+C2