a/ Vì \(x\ge3>-\frac{2}{3}\) nên giá trị biểu thức là :
\(x+\frac{2}{3}+x-3=2x-\frac{7}{3}\)
b/ Vì \(x>2>\frac{4}{3}>-\frac{2}{5}\) nên giá trị biểu thức là :
\(-\left(x+\frac{2}{5}\right)+\left(x-\frac{4}{3}\right)=-\frac{4}{3}-\frac{2}{5}=-\frac{26}{15}\)
tìm x biết :
a) \(\left(x+\frac{1}{2}\right).\left(\frac{2}{3}-2x\right)=0\)
b) \(\left(x.6\frac{2}{7}+\frac{3}{7}\right).2\frac{1}{5}-\frac{3}{7}=-2\)
c) \(x.3\frac{1}{4}+\left(-\frac{7}{6}\right).x-1\frac{2}{3}=\frac{5}{12}\)
d) \(5\frac{8}{17}:x+\left(-\frac{4}{17}\right):x+3\frac{1}{7}:17\frac{1}{3}=\frac{4}{11}\)
e) \(\frac{17}{2}-\left|2x-\frac{3}{4}\right|=-\frac{7}{4}\)
Tính nhanh
a) \(\frac{6}{7}:\left(\frac{1}{2}\text{X}\frac{3}{4}\right)-\frac{5}{8}\)
b) 34-2:\(\left(\frac{3}{5}-\frac{1}{2}\right)\)
c) \(\left(4\frac{1}{2}+\frac{1}{2}:5\frac{1}{2}\right)\text{X}\left(3\frac{5}{6}+2\frac{1}{6}\text{x}6\right)\)
+Tim x :
a ) \(\left(x-\frac{1}{2}\right)^3=\frac{1}{27}\)
b )\(\left(x+\frac{1}{2}\right)^2=\frac{4}{25}\)
c ) \(\left(x+1\right)^{x+2}=\left(x-1\right)^{x+6}\) (x ϵ Z )
d ) \(\left(2x+3\right)^{2016}=\left(2x+3\right)^{2018}\)
e ) \(\frac{3}{x+2.x+5}+\frac{5}{x+5.x+10}+\frac{7}{x+10.x+17}=\frac{x}{x+2.x+17}\) Với \(x\notin\left\{-2;-5;-10;-17\right\}\)
tìm số x , biết :
a) \(\frac{2}{3}x-\frac{3}{2}x=\frac{5}{12}\)
b) \(\frac{2}{5}+\frac{3}{5}.\left(3x-3,7\right)=\frac{-53}{10}\)
c) \(\frac{7}{9}:\left(2+\frac{3}{4}x\right)+\frac{5}{9}=\frac{23}{27}\)
d) \(\frac{-2}{3}.x+\frac{1}{5}=\frac{3}{10}\)
e) \(\left|x\right|-\frac{3}{4}=\frac{5}{3}\)
f) \(\left|2x-\frac{1}{3}\right|+\frac{5}{6}=1\)
tìm x biết :
a) \(\left(x+\frac{1}{5}\right)^2+\frac{17}{25}=\frac{26}{25}\)
b) \(-1\frac{5}{27}-\left(3x-\frac{7}{9}\right)^3=-\frac{24}{27}\)
c) \(\left(x+\frac{1}{2}\right).\left(\frac{2}{3}-2x\right)=0\)
tim x
\(a,\left|\frac{4}{7}-x\right|+\frac{2}{5}=0\)
\(b,6-\left|\frac{1}{4}x+\frac{2}{5}\right|=0\)
\(c,\left|x-\frac{1}{3}\right|+\left|2-\frac{4}{5}\right|=0\)
\(\frac{3}{\left(x+2\right).\left(x+5\right)}\) +\(\frac{5}{\left(x+5\right).\left(x+10\right)}\) + \(\frac{7}{\left(x+10\right).\left(x+5\right)}\)= \(\frac{x}{\left(x+2\right).\left(x+17\right)}\)
Câu 1:Tính A \(A=\left(1-\frac{1}{21}\right)\left(1-\frac{1}{28}\right)\left(1-\frac{1}{36}\right).....\left(1-\frac{1}{1236}\right)\)
Câu 2:
1.Tìm số nguyên x biết : \(\left|x^2-2\right|+\left|2-x^2\right|=28\)
2.Tìm số dư của \(A=776^{776}+777^{777}+778^{778}\) khi chia cho 3
Tìm x biết:
a) \(\frac{-3}{2}.\left(7-\frac{1}{6}\right)+4.\left(x-\frac{1}{2}\right)=3\)
b)\(3.\left(x-\frac{1}{5}\right)-7.\left(\frac{5}{14}-3\right)=20\)
Bạn nào làm ơn giúp mình có cách làm cho 4 tick