We all know that the algebraic formula 2x ^ 3 - Max ^ 2 + y ^ 2 is about the cubic trinomial of the letter x.y. the conditions for finding m, n are given It is known that the algebraic formula 2x ^ 3-max ^ 2 + y ^ 2 is a cubic trinomial about the letter x.y. the condition for finding m and N is given It is known that the algebraic formula 2x ^ 3 - mnx ^ 2 + y ^ 2 is a cubic trinomial of the letter x.y. the conditions for finding m and N are given.

We all know that the algebraic formula 2x ^ 3 - Max ^ 2 + y ^ 2 is about the cubic trinomial of the letter x.y. the conditions for finding m, n are given It is known that the algebraic formula 2x ^ 3-max ^ 2 + y ^ 2 is a cubic trinomial about the letter x.y. the condition for finding m and N is given It is known that the algebraic formula 2x ^ 3 - mnx ^ 2 + y ^ 2 is a cubic trinomial of the letter x.y. the conditions for finding m and N are given.

Mn is not equal to 0

If the M + n square + 4x-1 of the algebraic formula (m-n-4) x & sup3; + 2x is a quadratic trinomial, then the value of M, n is?

The coefficient of cubic term is 0, m-n-4 = 0
Then M-N = 4
The M + n power of 2x is a quadratic term, M + n = 2
Then M = (4 + 2) / 2 = 3
n=2-3=-1

If the value of - 3x & # 178; + MX + NX & # 178; - x + 3 is independent of the value of X, find the value of (M + n) (m-n)
Since the value of an algebraic expression has nothing to do with X, what is the value of an algebraic expression? What's x?

-3x²+mx+nx²-x+3=(-3+n)x²+(m-1)x+3
If the value of the above algebraic expression has nothing to do with the value of X, then:
-3+n=0,m-1=0
The solution is n = 3, M = 1
So: (M + n) (m-n) = (3 + 1) * (3-1) = 4 * 2 = 8
That is, when n = 3, M = 1, the algebraic formula - 3x & # 178; + MX + NX & # 178; - x + 3 = (- 3 + n) x & # 178; + (m-1) x + 3 = 3
It can be seen that no matter what value x takes, the value of the algebraic formula is always 3

(1) Square of x-4y + 2x-4y
(2) The second power of 14 (X-Y) - 7 (Y-X)

(1)
Original = (X & # 178; - 4Y & # 178;) + (2x-4y)
=(x+2y)(x-2y)+2(x-2y)
=(x-2y)(x+2y+2)
(2)
The original formula = 14 (X-Y) - 7 (X-Y) &# 178;
=7(x-y) [2-(x-y)]
=7(x-y)(2-x+y)

: 3 times of 5 is more than half of a number. 8 what is the number? List the equation and write the calculation process

Let this number be X
5*3-0.5X=8
15-0.5X=8
-0.5X=8-15
0.5X=7
X=7/0.5
X=14

16: What's the length and width of nine forty-two inches

One inch = 2.54 cm, that 42 inch is the length of diagonal, then 42inch is 42 * 2.54 = 106.68cm, that width: height = 16:9, that's OK. With Pythagorean theorem, suppose width is 16x, height is 9x, then 16x * 16x + 9x * 9x = 106.68 * 106.68 = 11380.6224, then x = 5.811229894, that width is 16x = 92.979

There are 200 pages in a story book. Xiao Zhang has read one fifth of the book, but there are still a few pages left

There are 200 pages in a story book. Xiao Zhang has read 1 / 5 of the book, and there are still 4 / 5 of the total pages left

Given 5A = 2B, 2C = 5b, find a than B than C

a=0.4b,c=2.5b,a:b:c=0.4:1:2.5=4:10:25

A small car and a large truck both drive from city a to city B. the large truck travels 50 kilometers per hour. The small car drives 4 hours later than the large truck, and the two cars arrive at city B at the same time. It is known that the distance between city a and city B is 400 kilometers. What is the speed of the small car? (using equation solution)

The car speed is set at XKM / h
（400/50 -4）x=400
x=100

The circumference of an isosceles triangle is 16cm, and the height of its bottom edge is 4cm

Waist 5 bottom 6
Set waist x bottom 16-2x
Bottom half 8-x
Pythagorean theorem (8-x) ^ 2 + x ^ 2 = 4 ^ 2
We get x = 5