Bài 1: Tính
A= $\frac{1}{1×2}$ + $\frac{1}{2×3}$ + $\frac{1}{3×4}$ +…+ $\frac{1}{49×50}$
Bài 2: TÌm x
a, /x/ – $\frac{3}{4}$ = $\frac{5}{3}$
b, /2x – $\frac{1}{3}$ / + $\frac{5}{6}$ = 1
c, $\frac{2}{3}$x – $\frac{3}{2}$x = $\frac{5}{12}$
d, ( x + $\frac{1}{5}$ ) ² +$\frac{17}{25}$ = $\frac{26}{25}$
Bài 1
A=1/1.2+1/2.3+1/3.4+...+1/49.50
A=1/1−1/2+1/2−1/3+1/3−1/4+...+1/49−1/50
A=1−1/5
A=49/50
Bài 2
a) X-3/4=5/3
X =5/3+3/4
X=29/12
b) 2X-3/2+5/6=1
2X-1/3 =1-5/6
2X-1/3 = 1/6
2X = 1/6+1/3
2X = 1/2
X= 1/2 :2
X= 1/4