x+2x+3x+4x+...+100x= (1+2+3+4+5+...+100)x=5050x!

Vay x= \(\frac{-213}{5050}\)

hihi k nha

\(\Leftrightarrow x\left(1+2+3+...+100\right)=-213\)

\(\Leftrightarrow x\cdot\frac{101\cdot100}{2}=-213\)

\(\Leftrightarrow5050x=-213\)

\(\Leftrightarrow x=-\frac{213}{5050}\)

x+2x+3x+...+100x=-213

x.(1+2+3+...+100)=-213

x[100.(100+1)/2]=-213

x.5050=-213

x=-213/5050

vậy x=-213/5050

a: =>5x-2=0 hoặc 2x+1/3=0

=>x=-1/6 hoặc x=2/5

b: Đặt x/2=y/3=k

=>x=2k; y=3k

xy=54

=>6k^2=54

=>k^2=9

=>k=3 hoặc k=-3

TH1: k=3

=>x=6; y=9

TH2: k=-3

=>x=-6; y=-9

c: =>5050x=-213

=>x=-213/5050

x+2x+3x+....+100x=-213

(1+2+3+...+100)x=-213

(\(\frac{100.\left(100+1\right)}{2}\))x=-213

5050.x=-213

x=-213:5050

x=-0,042 178 217

\(x+2x+3x+...+100x=-213\)

\(\Leftrightarrow x.\left(1+2+3+..+100\right)=-213\)

\(\Leftrightarrow x.[\frac{\left(100+1\right).100}{2}]=-213\)( áp dụng dãy số cách đều )

\(\Leftrightarrow x.5050=-213\)

\(\Leftrightarrow x=\frac{-213}{5050}\)

x + 2x + 3x + ... + 100x = -213

100x + 5050 = -213

100x = -213 - 5050 = -5263

x = -5263 : 100

x = -52,63

\(x+2x+3x+...+100x=-213\)

\(\Rightarrow x\times\left(1+2+3+...+100\right)=-213\)

\(\Rightarrow x\times5050=-213\)

\(\Rightarrow x=\frac{-213}{5050}\)

Vậy ...

1

a)<=> 3x-5-x=0

   <=>    2x-5=0

   <=>        x=5/2

c) x.(1+2+3+4+...+100)=0

    x.5050=0

     x=0:5050=0

Vậy x=0

d) x.(1+2+3+4+5+...+100)=5050

    x.5050=5050

    x=1

Vậy x=1

e) x+1+x+2+x+3+x+4+...+x+100=5050

    (x+x+x+x+...+x)+(1+2+3+4+...+100)=5050

     100 số hạng x

    x.100+5050=5050

    x.100=0

    x=0

Vậy x=0

a , x = \(\frac{5}{2}\)