The function f (x) = √ (1-A & # 178;) x & # 178; + 3 (1-A) x + 61. If the domain of F (x) is r, the range of a is obtained 2. If the domain of F (x) is [- 2,1], find the value of real number a

The function f (x) = √ (1-A & # 178;) x & # 178; + 3 (1-A) x + 61. If the domain of F (x) is r, the range of a is obtained 2. If the domain of F (x) is [- 2,1], find the value of real number a

You can do that
The definition field of y = LNX is x > 0, why? Because when x ≤ 0, this function has no meaning
Similarly, the function f (x) must be meaningful. So, √ (1-A & # 178;) ≥ 0 is necessary
It is found that - 1 ≤ a ≤ 1
Looking back, if there are no restrictions, just look at the expression of this function. The domain of F (x) is r
OK, let's change the domain now. Is it useful? It's irrelevant to the value of A
x. The transformation of a can affect the value of function, the change of X obviously can't affect the value of a, the unknown range is the key
Well, you say

If the value range of X in the function f (X & # 178;) is - 1 ≤ x ≤ 1, find the definition field of F (x)

-1≤x≤1
0≤x²≤1
The domain is [0,1]

7. If the domain of function f (x) is [0,1], then the domain of function g (x) = f (X & # 178;) / X-1 is

The solution is g (x) = f (X & # 178;) / X-1
So x ^ 2 belongs to [0,1]
X belongs to [- 1,1]
But when x = 1, the denominator X-1 = 0, so it cannot be taken
The definition field of function g (x) = f (X & # 178;) / X-1 is [- 1,1)

Finding the total differential of the function z = x ^ 2Y ^ 3 + 3

Z'x=2xy^3
Z'y=3x^2y^2
dz=Z'xdx+Z'ydy=(2xy^3)dx+(3x^2y^2)dy

10 times 11:3 plus 11 times 12:3 plus 12 times 13:3 What's the rule of this problem?

=3×(1/10×11+1/11×12+…… +1/19×20)
=3×(1/10-1/11+1/11-1/12+…… +1/19-1/20)
=3×(1/10-1/20)
=3/20

Find the formula of area, perimeter and volume
I can't remember many formulas. I'd like to ask my brothers and sisters to help me. I only need triangle, square, circle, rectangle, parallelogram, trapezoid and other plane figures in primary school

S (triangle) = bottom × height △ 2
S (square) = side length × side length
S (circle) = π R ^ 2
S (rectangle) = length × width
S (parallelogram) = base × height
S (trapezoid) = (upper bottom + lower bottom) × height △ 2

Why does Taylor formula of one variable function have n!
Why not use f (x0) + F '(x0) (x-x0) + F' '(x0) (x-x0) ^ 2 + What about approaching?
Is it true that Taylor series was tried out at the beginning, or how to approach it based on image analysis? In other words, how did the third item come out!

Because f (x0) + F '(x0) (x-x0) + F' '(x0) (x-x0) ^ 2 + The result of is not equal to f (x)
At the beginning, Taylor calculated the derivative of order n for y = f (x) = x ^ n, expanded it at x0 = 0, and found that n needs to be added!

The specific heat capacity of water is: C=______ J / (kg ·℃), the physical meaning of which is______ ．

The specific heat capacity of water is 4.2 × 103J / (kg ·℃). Its physical meaning is that the heat absorbed (or released) by 1kg of water increases (or decreases) 1C is 4200j. So the answer is: 4.2 × 103; the heat absorbed (or released) by 1kg of water increases (or decreases) 1C is 4200j

What is the unit of acceleration formula F = ma, a

M ` 2 / s square second

Inequality of logarithmic function
Log is based on half (x + 2)

-1