\(\frac{\left|-5\right|.7^4+7^3.25}{7^5.125-7^3.50}\)

Đề bài là như thế này à bạn? Hoàng Uyên Thảo

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Ta có: \(B=\frac{\frac19-\frac17-\frac{1}{11}}{\frac49-\frac47-\frac{4}{11}}+\frac{0,6-\frac{3}{25}-\frac{3}{125}-\frac{3}{625}}{\frac45-0,16-\frac{4}{125}-\frac{4}{625}}\)

\(=\frac{\frac19-\frac17-\frac{1}{11}}{4\left(\frac19-\frac17-\frac{1}{11}\right)}+\frac{\frac35-\frac{3}{25}-\frac{3}{125}-\frac{3}{625}}{\frac45-\frac{4}{25}-\frac{4}{125}-\frac{4}{625}}\)

\(=\frac14+\frac{3\left(\frac15-\frac{1}{25}-\frac{1}{125}-\frac{1}{625}\right)}{4\left(\frac15-\frac{1}{25}-\frac{1}{125}-\frac{1}{625}\right)}\)

\(=\frac14+\frac34=\frac44=1\)

\(=\dfrac{\dfrac{1}{9}-\dfrac{1}{7}-\dfrac{1}{11}}{4\left(\dfrac{1}{9}-\dfrac{1}{7}-\dfrac{1}{11}\right)}+\dfrac{3\left(\dfrac{1}{5}-\dfrac{1}{25}-\dfrac{1}{125}-\dfrac{1}{625}\right)}{4\left(\dfrac{1}{5}-\dfrac{1}{25}-\dfrac{1}{125}-\dfrac{1}{625}\right)}\)

\(=\dfrac{1}{4}+\dfrac{3}{4}=\dfrac{4}{4}=1\)

1,5+1-0,75

a) 4.25-12.5+170:10

=100-60+17

=40+17

=57

b) (7+3³:3²).4-3

=(7+3).4-3

=10.4-3

=40-3

=37

c) 12:{400:[500-(125+25.7)]}

=12:{400:[500-(125+175)]}

=12:{400:[500-300]}

=12:{400:200}

=12:2

=6

d) 168+{[2.(2⁴+3²)-256⁰]:7²}

=168+{[2.(16+9)-1]:49}

=168+{[2.25-1]:49}

=168+{[50-1]:49}

=168+{49:49}

=168+1

=169

Sửa đề: \(5^9\cdot49^2\)

\(=\dfrac{5^{10}\cdot7^3-5^9\cdot7^4}{5^9\cdot7^3+5^9\cdot14^3}-\dfrac{2^{12}-2^{12}\cdot3^4}{2^{12}\cdot3^6+2^{12}\cdot3^5}\)

\(=\dfrac{5^9\cdot7^3\left(5-7\right)}{5^9\cdot7^3\left(1+8\right)}-\dfrac{2^{12}\left(1-3^4\right)}{2^{12}\left(3^6+3^5\right)}=\dfrac{-2}{9}+\dfrac{80}{972}\)

=-34/243