Y is proportional to x, when x = 5, y = 6, find the analytic expression of the function y = KX + B

Y is proportional to x, when x = 5, y = 6, find the analytic expression of the function y = KX + B

Because y is proportional to x, B = 0
When x = 5, y = 6 is brought into the analytical formula
6=5k+b
b=0
So k = 6 / 5
So the analytic expression is equal to
y=6/5x

F (z) = u + IV is an analytic function, where (1) v = 2XY + 3x; (2) u = 2 (x-1) y, f (0) = - I, the analytic function f (z) is requested

(1) And we will be able to get 8706; V / \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\- I  f (z) = Z & # 178; + 3iz-i (2

If the function f (x) = loga (x2 − ax + 2) is positive in the interval (1, + ∞), then the value range of real number a is ()
A. （1，2）B. （1，2]C. （0，1）∪（1，2）D. (1，52)

∵ the function f (x) = loga (x2-ax + 2) is always positive in the interval (1, + ∞). When x ＞ 1, f (x) = loga (x2-ax + 2) ＞ loga1. When 0 ＜ a ＜ 1, 0 ＜ a ＜ 112 − a × 1 + 2 ≤ 1, there is no solution; when a ＞ 1, a ＞ 112 − a × 1 + 2 ≥ 1, the solution is 1 ＜ a ≤ 2

The length of the locomotive is equal to the length of the guard car plus half of the car. The length of the car is equal to the length of the guard car plus the length of the locomotive. How long is the locomotive, car and guard car of the train?

The length of the carriage is x meters
The length of locomotive is 6.4 + X / 2
Car length: x = 6.4 + 6.4 + X / 2
The solution is x = 25.6
The locomotive length is 6.4 + 25.6 / 2 = 19.2
Therefore, the total length of locomotive, carriage and guard car = 19.2 + 25.6 + 6.4 = 51.2m

Some space geometry problems
1. In the pyramid p-abcd, PA is perpendicular to the plane ABCD, the bottom surface ABCD is a right angled trapezoid, AB is perpendicular to ad, CD is perpendicular to ad, CD = 2Ab, e is the midpoint of PC
2. In the pyramid p-abcd, the quadrilateral ABCD is a square, the projection of point P in the plane ABCD is a, and PA = AB = 2, e is the midpoint of PD. It is proved that (1) Pb is parallel to the plane AEC, and (2) PCD is perpendicular to the plane pad

1. (1) because PA is perpendicular to the plane ABCD, CD is contained in the plane ABCD, so PA is perpendicular to CD, and CD is perpendicular to ad, and ad intersects PA, so according to the line plane perpendicularity judgment theorem, CD is perpendicular to the plane pad, and CD is contained in the plane PCD. So the plane PDC is perpendicular to the plane pad (2), and the midpoint of PD is f, connecting EF and AF. because e, F. are the midpoint of PC and PD, EF is parallel and equal to 1 / 2CD, and ab is parallel and equal to 1 / 2CD, So EF is parallel and equal to AB, so abef is a parallelogram, that is AF parallel EF, according to the line plane parallel theorem, be parallel pad
2. (1) connect AC and BD. let the intersection point be o and connect OE. Because o and E are the midpoint of BD and PD, OE is parallel to ab. according to the line plane parallel theorem, Pb is parallel to AEC,
(2) If the projection of point P in the plane ABCD is a, then PA is perpendicular to the ground ABCD, and CD is included in the plane ABCD, so CD is perpendicular to PA, and CD is perpendicular to AD. according to the line plane verticality judgment theorem, CD is perpendicular to the plane pad, and CD is included in the plane PCD, so the plane PCD is perpendicular to the plane pad

2 (the square of a - AB) - the square of 2A + 3AB
Answer the questions in five minutes. Ten

2 (the square of a - AB) - the square of 2A + 3AB
=The square of 2a-2ab-2a + 3AB
=ab

If the second derivative of function f (x) exists and F "(x) > 0, then f (x) = [f (x) - f (a)] / [x-a] is in (a, b]

F "(x) > 0, f '(x) is an increasing function, f (x) = [f (x) - f (a)] / [x-a] = KMA is an increasing function

Help me with three math problems,
(1)5^n+1÷5^3n+1
(2)10^5÷10^-1×10^0
(3)(1/3)^0÷(-1/3)^-2

(1)5^(n+1)÷5^(3n+1)
=5^(n+1-3n-1)
=5^(-2n)
=(1/25)^n
(2)10^5÷10^(-1)×10^0
=10^(5+1+0)=10^6=1000000
(3)(1/3)^0÷(-1/3)^-2
=(1/3)^0÷(1/3)^-2
=(1/3)^(0+2)
=(1/3)^2
=1/9

If the axis of symmetry of the quadratic function y = x2-bx + 2 is a straight line x = 2, then B =? 2, the formula of the quadratic function y = x & # 178; - 2x-1 is expressed as a vertex?
3. The vertex coordinate of the image of the quadratic function is (- 2,3), and its shape and opening direction are the same as that of the parabola y = - X & # 178; the analytic formula of the quadratic function is? 4, the parabola y = x & # 178; - 4x + M vertex is on the x-axis, and its vertex coordinate is? 5. Given that the parabola passes through (- 2,5) and (4,5), then its axis of symmetry is?

1, the symmetry axis of the quadratic function y = x2-bx + 2 is a straight line x = 2, then B = 4.2, the formula of the vertex formula of the quadratic function y = x & # 178; - 2x-1 is y = (x-1) &# 178; - 2.3, the vertex coordinate of the image of the quadratic function is (- 2,3), its shape and opening direction are the same as the parabola y = - X & # 178; the analytic formula of the quadratic function is

The derivative of y = xsinx ＋ x

Do it according to the formula
Formula: [f (x) * g (x)] '= f' (x) * g (x) + F (x) * g '(x)
(power n of x) '= n * (power N-1 of x)
Y '= SiNx + xcosx + 0.5 * (1 / x under root)