Three people went to the hotel, each 10 yuan, the boss said discount, returned 5 yuan, the waiter private possession of 2 yuan, give them a person 1 yuan, equivalent to everyone spent 9 yuan

Three people went to the hotel, each 10 yuan, the boss said discount, returned 5 yuan, the waiter private possession of 2 yuan, give them a person 1 yuan, equivalent to everyone spent 9 yuan

First way of understanding:
Thirty nine is twenty-seven yuan. The boss only charged twenty-five yuan. The waiter embezzled two yuan. Isn't that right?
The amount of money each guest takes out = the amount of money collected by the boss + the amount of money embezzled by the waiter
Second way of understanding:
25+1+1+1+2=30
All the money is on four people, boss 25, three people, one person, waiter 2, just 30

First simplify and then evaluate x ^ 2-1 / x ^ 2-2x + 1 △ x + 1 / X-1 × 1-x / 1 + X

=(x+1)(x-1)/(x-1)² ×(x-1)/(x+1) ×(1-x)/(1+x)
=(x+1)/(x-1) ×(x-1)/(x+1) ×(1-x)/(1+x)
=(1-x)/(1+x)

Simplification: (x + 1) 2-2x=______ ．

The original formula = x2 + 2x + 1-2x = x2 + 1

Simplification (1 / 2x + 1) (X-2)

x-1/x-3/2

Simplification (x ^ 2-1) (x + 1) / x ^ 2-x △ 1 + x ^ 2 + 1 / 2x)

（x^2-1)(x+1)/(x^2-x) / (1+x^2+1/2x) =[(x-1)(x+1)/x(x-1)] / [(2x+x^2+1)/2x] =[(x+1)/x)] / [(x+1)^2/2x] =(x+1)/x*2x/(x+1)^2 =2/(x+1)

Simplify 1 / 2x-1 / x + y (x + Y / 2x-x-y)

Original formula = 1 / 2x-1 / (x + y) [(x + y) / 2x - (x + y)]
=1/2x-1/(x+y)×(x+y)(1/2x-1)
=1/2x-(1/2x-1)
=1/2x-1/2x+1
=1

Simplify (x ^ 2-2x + 1) / (x ^ 2 + 1) / (x-1) / (x ^ 2 + x) - x

Do you make a mistake about a sign (x ^ 2-2x + 1) / (x ^ 2 - 1) / (x ^ 2 + x) - x = (x-1) &# 178; / (x + 1) (x-1) × x (x + 1) / (x-1) - x = x-x = 0 (x ^ 2-2x + 1) / (x ^ 2 + 1) / (x ^ 2 + x) - x = (x-1) &# 178; / (X & # 178; + 1) × x (x + 1) / (x-1) - x = x (x + 1) (x-1) / (X & # 17

Reduction of (x-1) (2x-1) - (x + 1) to the second power + 1

（x-1）（2x-1）-（x+1）²+1
=x×2x+x×（-1）+（-1×2x）+（-1）×（-1）-（x²+2x+1）+1
=2x²-x-2x+1-x²-2x-1+1
=x²-5x+1

Simplify the quintic power of (2x-1) + the quintic power of (2x + 1)
Need a complete process! Thank you!

Original form
=(32x5-90x4+80x3-40x2+10x-1)+(32x5+90x4+80x3+40x2+10x+1)
=64x5+160x3+20x

Simplified evaluation: (x ^ 2-y ^ 2) / X multiplied by 2x / (x ^ 2-2xy + y ^ 2), where x = 2, y = 1

=(x+y)(x-y)/x×2x/(x-y)²
=(x+y)×2/(x-y)
=2(x+y)/(x-y)
=6