Question

tìm x : 

a) I x+1/101I+ I x+2/101 I +.........+ I x+100/101I = 101x

b) I x+5I- I1-2xI =x 

Answer 1

a) Để đẳng thức xảy ra thì: 101x\(\ge\)0=>x\(\ge\)0

Suy ra: \(x+\frac{1}{101}+x+\frac{2}{101}+....+x+\frac{100}{101}=101x\)

<=>\(100x+\frac{1+2+....+100}{101}=101x\)

<=>x=\(\frac{\frac{\left(1+100\right).100}{2}}{101}=50\)

 

Answer 2

phan b lap bang xet dau

x -5 0,5

x+5 0 /

1-2x / 0

voi x<-5 ta co pt: -x-5-1+2x=x

-6=0(loai)

voi -5=<x=<0,5 :x+5-1+2x=x

2x=-2(nhan)

voi x>0,5: x+5+1-2x=x

x=3(nhan)