Given the vector a = (x-1,3), B = (3, y), if a ⊥ B, then the maximum value of XY is

1/4

It is known that the function f (x) is an odd function with period 3 whose domain is r, and when x ∈ (0,1.5), f (x) = ln (x2-x + 1), then the number of solutions of the equation f (x) = 0 in the interval [0,6] is ()
A. 3B. 5C. 7D. 9

∵ when x ∈ (0, 1.5), f (x) = ln (x2-x + 1), Let f (x) = 0, then x2-x + 1 = 1, the solution is x = 1, and ∵ the function f (x) is an odd function whose domain is r, ∵ in the interval ∈ [- 1.5, 1.5], f (- 1) = f (1) = 0, f (0) = 0f (1.5) = f (- 1.5 + 3) = f (- 1.5) = f (- 1.5) ∵

Find the maximum value of the function y = 1 / (2x - 4) in the interval [3,5]

In the interval [3,5], 2X-4 is greater than zero and monotonically increases, so the function y = 1 / (2X-4) monotonically decreases in the interval [3,5]
So the maximum value is f (3) = 1 / (2 * 3-4) = 1 / 2

For the function f (x) = - 1 / 4x4 + 2 / 3x3 + ax2-2x-2
Where a is a real constant, and the tangent of the image of the function y = f (x) at the point (- 1, f (- 1)) is perpendicular to the Y axis (1) 0, find the value of the real number a (2) if the equation f (degree x of 3) = m about X has three unequal real roots, find the value range of the real number m (3) if the function y = log2 (f (x) + P) has no zero point, find the value range of the real number P
Log is based on 2
F (x) = minus one fourth of x plus two thirds of x plus ax minus 2x minus 2

(1) ∵ given the function y = f (x), the tangent of the image at the point (- 1, f (- 1)) is perpendicular to the Y axis
The tangent slope of the image with y = f (x) at the point (- 1, f (- 1)) is 0
∵f'(x)=-x^3+2x^2+2ax-2
The derivative of F (x) at (- 1, f (- 1)) & nbsp; F & # 39; (- 1) = 1-2a = 0 & nbsp; & nbsp; & nbsp;; a = 1 / 2
(2) f(x)=-x^4/4+2x^3/3+x^2/2-2x-2 f'(x)=-x^3+2x^2+x-2
=-(x+1)(x-1)(x-2)
Let 3 ^ x = T & nbsp; & nbsp; & nbsp;, then & nbsp; t > 0 & nbsp; & nbsp; F & # 39; (T) = - (T + 1) (t-1) (T-2) = 0 & nbsp; & nbsp; & nbsp; & nbsp; t = - 1 & nbsp;, & nbsp; 1 & nbsp;, & nbsp; 2
On & nbsp; & nbsp; & nbsp; 1 < T < 2 & nbsp; & nbsp;, f (T) is an increasing function on & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 0 < T < 1 & nbsp; & nbsp; and & nbsp; & nbsp; t > 2
F (0) = - 2 F (1) = - 37 / 12 f (2) = - 8 / 3
Image combined with F (T) & nbsp; & nbsp; & nbsp; (as shown in the figure:) & nbsp; & nbsp; (Note: the image is not very similar)
It is easy to know that f (T) = M & nbsp; & nbsp; & nbsp; & nbsp; - 37 / 12 ＜ m ＜ - 2 when there are three unequal real roots
(3) It is known from (2) that f (x) max = - 5 / 12;
When f (x) + P ≤ 0 is constant, the function y = log2 (f (x) + P) has no zero
Then f (x) MAX + P = - 5 / 12 + P ≤ 0 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp;: P ≤ 5 / 12
② If there is f (x) + P > 0, then the function y = log2 (f (x) + P) has no zero point, and the solution is obtained
③ When f (x) + P ≥ 1, f (x) is a continuous function
For any P & nbsp; & nbsp; & nbsp;, there must be an X & nbsp; & nbsp; & nbsp; such that & nbsp; & nbsp; f (x) + P = 1 & nbsp; & nbsp;
That is to say, the function y = log2 (f (x) + P) has zeros, which does not meet the condition;
To sum up, P < 17 / 12

It is known that A.B.C is not equal to 0, and the maximum value of a / | a | + B / | B | + C / | C | + ABC / | ABC |, is m, and the minimum value is n, then (M + n) 2005
(2005 in the upper left corner)

The maximum value of 4 is all positive
The minimum value - 4 is all negative
(m+n)^2005=0

In mathematics, it is stipulated that rational numbers are represented on the number axis in the order from left to right

It is stipulated in mathematics that rational numbers are represented on the number axis, and their order from left to right is the order from small to large, that is, the number closer to the left on the number axis is smaller, and the number closer to the right is larger

What does ABCD of y = (Cx + D) / (AX + D) of the graph of a fractional function mean
The more detailed, the better

Is the denominator ax + B?
There is no relationship between ABCD
If C / D = A / B, then y = C / A is a constant
If it's not equal,
Function has two asymptotes x = - A / B, y = C / A, symmetry center (- A / B, C / a)

In English, it means multiple + the + noun + of structure. Is the predicate singular or plural

Use the singular, because no matter how much it is, it's just a whole

As shown in the figure, make the figure of △ ABC rotated 180 ° about point O. (do not write the method, keep the trace of drawing)

Is there any synonym for this word

There are several grammatical mistakes in the one upstairs
Is there any synonym for this word?
Does this word have any synonyms?
We should use have instead of has, because synnyms are plural
This is the right way to translate. Please adopt your own translation in time;

Given the vector a = (x-1,3), B = (3, y), if a ⊥ B, then the maximum value of XY is