một yếu tố lẻ 74, bên cạnh 1

3357;3375;3537;3573;3735;3753;5337;5733;5373;7335;7353;7533

=3².2².3⁴.2⁴-2⁶(3⁶-1)

=2⁶.3⁶-2⁶(3⁶-1)

=2⁶(3⁶-3⁶+1)=2⁶=64

Mk bít nhưng ko dám nói ra đâu, vô duyên lém!

\(=\dfrac{\dfrac{1}{3}-\dfrac{1}{7}-\dfrac{1}{13}}{2\left(\dfrac{1}{3}-\dfrac{1}{7}-\dfrac{1}{13}\right)}.\dfrac{\dfrac{1}{3}-\dfrac{1}{4}+\dfrac{1}{5}}{\dfrac{7}{6}-\dfrac{7}{8}+\dfrac{7}{10}}+\dfrac{6}{7}\)

\(=\dfrac{1}{2}.\dfrac{\dfrac{1}{3}-\dfrac{1}{4}+\dfrac{1}{5}}{\dfrac{7}{2}\left(\dfrac{1}{3}-\dfrac{1}{4}+\dfrac{1}{5}\right)}+\dfrac{6}{7}\)

\(=\dfrac{1}{2}.\dfrac{2}{7}+\dfrac{6}{7}=\dfrac{1}{7}+\dfrac{6}{7}=1\)

tên là quân phải ko?còn bn là hương

a) 16<4ⁿ<256

<=> 4²<4ⁿ<4⁴ => n=3

(x+1)⁴=81=3⁴

=>x+1=3

=>x=2

\(x\cdot\frac{1}{2}-x=\frac{2}{3}\)

\(x=\frac{\frac{2}{3}}{-\frac{1}{2}}\)

\(x=\frac{-4}{3}\)

=12x⁵y³-2x⁴y³+3xy²

=5(1/2+1/6+1/12+1/20+1/30+1/42+...+1/110)

=5(1/1.2+1/2.3+1/3.4+1/4.5+1/5.6+1/6.7+1/10.11)

=5(1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+...+1/10-1/11)

=5(1-1/11)=5.10/11=50/11