3個人去住飯店,每個人10元,老闆說優惠,退了5元,服務員私藏了2元,給他們一人1元,相當於每個人花了9元

3個人去住飯店,每個人10元,老闆說優惠,退了5元,服務員私藏了2元,給他們一人1元,相當於每個人花了9元


第一種理解管道:
三九就是二十七元.老闆只收了二十五元.服務員私吞了二元.這樣帳不就對了嗎?
客人每人拿出的錢數=老闆收的錢數+服務員私吞的錢數.
第二種理解管道:
25+1+1+1+2=30
錢都在四個人身上老闆25三人一人1服務員2正好30



先化簡再求值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)



化簡:(x+1)2-2x=______.


原式=x2+2x+1-2x=x2+1.故答案為:x2+1



化簡(1/2x+1)(x-2)


x-1/x-3/2



化簡(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)



化簡1/2x-1/x+y(x+y/2x-x-y)


原式=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



化簡(x^2-2x+1)/(x^2+1)÷(x-1)/(x^2+x)-x


你是不是搞錯了一個符號(x^2-2x+1)/(x^2 - 1)÷(x-1)/(x^2+x)-x=(x-1)²;/(x+1)(x-1)×x(x+1)/(x-1)-x=x-x=0(x^2-2x+1)/(x^2+1)÷(x-1)/(x^2+x)-x=(x-1)²;/(x²;+1)×x(x+1)/(x-1)-x=x(x+1)(x-1)/(x…



(x-1)(2x-1)-(x+1)的2次方+1化簡


(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



化簡(2x-1)的5次方+(2x+1)的5次方
需要完整的過程!謝謝!


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



化簡求值:(x^2-y^2)/x乘以2x/(x^2-2xy+y^2),其中x=2,y=1


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