a) ( x + 1) + ( x + 3) + ( x + 5 ) + …+ ( x + 99) = 0;
b) ( x – 3) + ( x - 2) + ( x – 1 ) + …+ 10 + 11 = 11;
c) x x x 1 2 ... 2018 2019 2019 ;
a, ( x+1)+ (x+3)+(x+5) +...+(x+99)= 0
b, (x-3) + ( x-2)+ ( x-1)+ ...+ 10+11 =0
1, Tìm x biết :
a,( x +1 ) + (x+3) +( x+ 5) + ...... +( x + 99) -0
b, (x -3 )+ ( x -2 ) +( x- 1) +........+ 10+11 =0
2, Tìm x biết :
a, (x+1) + (x+3) + (x+5) +.......+(x+99) =0
b, (x -3) + (x -2) + (x-1) +........+10 +11=0
a, (x+1) + (x+3) + (x+5) +.......+(x+99) =0
\(\Rightarrow\)x+x+x+...+x(50 số hạng) + 1+3+5+...+99=0
\(\Rightarrow\)50.x+4950=0
50.x=0-4950
50.x=(-4950)
x=(-4950):50
x=(-99)
Tìm x biết :
a) (x+1)+(x+3)+(x+5)+...+(x+99)=0
b) (x-3)+(x-2)+(-1)+...+10+11=0
a) (x-7)(x+3)<0
b) (x+1)+(x+3)+(x+5)+.....+(x+99)=9
a/ (x+1)+(x+3)+(x+5)+....+(x+99)=0
b/ (x-3)+(x-2)+(x-1)+...+10+11=11
Tìm x?
a/ 99x+(1+2+...+99)=0
99x+(1+99)x49,5=0
x=5
b/3x-1-2-3+1+2+3+4+...+10=0
3x+4+5+...+10=0
x=-49/3
Bài 1:
a, A=1+(-2)+(-3)+4+5+(-6)+(-7)+8+...+99-100-101+102+103
b, B=1+(-3)+5+(-7)+...+97+(-99)+101
Bài 2:
a,|x+2|-x=2
b,|x-3|+x-3=0
c, |x+1|+|x+2|=1
d,|x-5|+x-8=6
1
b;
B=1+ (7-5) + (11-9) + ...+(101-99)
B=1+2+2+..+2
B=1+25.2=51
2.
a.
ĐK : x+2 >=0 => x>=-2
\(\left|x+2\right|-x=2\\ \Rightarrow\left|x+2\right|=2+x\\ \Rightarrow\left[{}\begin{matrix}x+2=x+2\\x+2=-x-2\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}0x=0\\2x=-4\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}0x=0\\x=-2\end{matrix}\right.\)
Vậy x=-2
2.
d;
\(\left|x-5\right|\)=14-x
\(\Leftrightarrow\left[{}\begin{matrix}x-5=14-x\\x-5=x-14\end{matrix}\right.\)
em giải 2 cái này ra để tìm x
tìm x
a)(x+1)+(x+3)+(x+5)+...+(x+99)=0
b)(x-3)+(x-2)+(x-1)+...+10+11=11
a,(x+x+x+...+x)+(1+3++5+...+99)=0
có 50 số có 50 số
50x+(99+1)*50/2=0
50x+2500=0
50x=0-2500
50x=-2500
x=-2500/50
x=-50
Vậy x=-50
1.a)(x+3/5).(x+1)<0
b)(x-1/3).(x+2/5)>0
2.B=(1-2/5).(1-2/7).(1-2/9).....(1-22/99)
tìm x;y biết
a, (x+1).(5-x)=3
b, (2x+1).(3y-2)=-55
c, (x+1)+(x+3)+(x+5)+...+(x+99)=0
d, (x-4).(x+9)<0