5 - 0 x 3 + 9 : 3 = 5 - 0 + 3 = 5 + 3 = 8
5 - 0 x 3 + 9 : 3 = 5 - 0 + 3 = 5 + 3 = 8
\(A=\frac{3}{1\times1\times2\times2}+\frac{5}{2\times2\times3\times3}+...+\frac{19}{9\times9\times10\times10}\)
\(1\frac{1}{24}\times3\frac{2}{5}+1\times3\frac{7}{9}+\frac{10}{11}=?\)
Tính (Theo mẫu):
MẪU\(\frac{9}{10}\times\frac{5}{6}=\frac{9\times5}{10\times6}=\frac{3\times3\times5}{5\times2\times3\times2}=\frac{3}{4}\)\(\frac{3}{4}\)
\(\frac{12}{35}\div\frac{35}{25}\)
\(\frac{9}{22}\times\frac{33}{18}\)
Tính nhanh:\(\frac{1\times2\times3+2\times4\times6+3\times6\times9+4\times8\times12+5\times10\times15}{1\times3\times5+2\times6\times10+3\times9\times15+4\times12\times20+5\times15\times25}-\frac{1+2+3+2+4+6+3+6+9+4+8+12+5+10+15}{1+3+5+2+6+10+3+9+15+4+12+20+5+15+25}\)
a) x10 = 1 ; b) 2x = 256 ; c) x10 = x ; d) ( 2x - 15 )5 = (2x - 15)3 ; e)\(\frac{11\times3^{22}\times9\times35-9\times15}{\left(2\times3^{14}\right)^2}\)
Tính nhanh
\(\frac{2}{1\times3}+\frac{2}{3\times5}+\frac{2}{5\times7}+\frac{2}{7\times9}+\frac{2}{9\times11}\)
\(\left(\frac{4}{1\times3}+\frac{4}{3\times5}+\frac{4}{5\times7}+\frac{4}{7\times9}\right)\times10-x=0\)
\(B=\dfrac{1}{1\times2}+\dfrac{1}{2\times3}+\dfrac{1}{9\times10}\)
Tìm x biết \(\left(\frac{1}{1\times2}+\frac{1}{2\times3}+\frac{1}{3\times4}+\frac{1}{4\times5}+\frac{1}{5\times6}\right)\times10-x=0\)