Thu gọn các đơn thức sau,xác định hệ số và tìm bậc
a) \(\dfrac{1}{2}\)( \(^{x^3}\)).(\(\dfrac{-3}{4}\))\(^{x^2}\)
b) (-2x)\(^{^2}\).(\(\dfrac{1}{2}\))\(^{^3}\)
c) (\(\dfrac{4}{5}\)x)\(^{^2}\).\(\dfrac{15}{2}\).\(^{x^3}\)
d) \(\dfrac{2}{9}^{x^2}\).(\(\dfrac{3}{2}\))\(^{^2}\)
e) (\(\dfrac{3}{5}\)x)\(^{^2}\).(\(\dfrac{5
}{2}\)\(^{x^3}\))\(^{^2}\)
GIÚP MIK VỚI MIK ĐANG CẦN GẤP GẤP!!!THANKS MỌI NGƯỜI
CMR với n thuộc Z, có:
\(\left(1+\dfrac{1}{2}\right).\left(1+\dfrac{1}{5}\right).\left(1+\dfrac{1}{9}\right)...\left(1+\dfrac{2}{n^2+3n}\right)< 3\)
Cho \(f\left(x\right)=x^2+x\)
Tính \(\dfrac{1}{f\left(1\right)}+\dfrac{1}{f\left(2\right)}+\dfrac{1}{f\left(3\right)}+...+\dfrac{1}{f\left(2014\right)}+\dfrac{1}{f\left(2015\right)}\)
CMR: \(\dfrac{1}{3}-\dfrac{2}{3^2}+\dfrac{3}{3^3}-\dfrac{4}{3^4}+...+\dfrac{99}{3^{99}}-\dfrac{100}{3^{100}}< \dfrac{3}{16}\)
Cho \(A=\left(1+\dfrac{1}{2}+\dfrac{1}{3}+...+\dfrac{1}{97}+\dfrac{1}{98}.2014^{2015}\right)\)
CMR: A ⋮ 11.
Tìm x: \(\left|x+\dfrac{1}{3}\right|+\left|x+\dfrac{2}{3}\right|+\left|x+\dfrac{2}{5}\right|+\left|x+\dfrac{3}{2}\right|=33x\)
\(\dfrac{1}{3}x-\dfrac{2}{5}\left(x+1\right)=0\)
\(\dfrac{x+2}{0,5}=\dfrac{2x+1}{2}\)
Tim x
giai giup nhe, mai phai nop roi :(
Bài 1 ;Tính :
B = \(512-\dfrac{512}{2}-\dfrac{512}{2^2}-\dfrac{512}{2^3}-...-\dfrac{512}{2^{10}}\)
\(\dfrac{x}{x+2}\) =\(\dfrac{x+5}{x+1}\)
\(\dfrac{x-4}{2}=\dfrac{3x+1}{3}\)