Bài 1: a) Tính tổng \(M=3\frac{1}{417}.\frac{1}{762}-\frac{1}{139}.4\frac{761}{762}-\frac{4}{417.762}+\frac{5}{139}\)
b, Tính giá trị của đa thức sai tại x=-1 : \(x^2+x^4+x^6+x^8+....+x^{100}\)
tìm x
a) x+10=25
b)\(\frac{2}{3}\)x-\(\frac{1}{2}\)=\(\frac{1}{10}\)
c)\(\frac{x}{7}\)=\(\frac{-6}{21}\)
d)|\(\frac{2}{3}\)x-\(\frac{1}{2}\)|=\(\frac{5}{6}\)
cho \(\frac{x}{2}=\frac{y}{3}=\frac{z}{4}\)
tinh P=\(\frac{y+z-x}{x-y+z}\)
Làm tính nhân
a) ( -5x2 ) ( 3x3 - 2x2 + x - 1 )
b) ( -43 + \(\frac{2}{3}y\) - \(\frac{1}{4}yz\) ) ( \(-\frac{1}{2}xy\) )
(1+2+3+4+...+100)\(\times\)(18,34-9,68):(\(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{100}\))
Giúp mik với!~~~
\(\frac{4}{9}:\left(\frac{-1}{7}\right)+6\frac{5}{9}.\left(\frac{2}{3}\right)\)
Tìm x:
\(\dfrac{x}{-18}=\dfrac{-50}{x};\\ 1\dfrac{1}{3}:\left(-0,08\right)=\dfrac{2}{3}:\left(-0,1x\right);\\ x=\dfrac{a}{b+c}=\dfrac{b}{c+a}=\dfrac{c}{b+a};\\ \dfrac{x^2}{6}=\dfrac{24}{25};\dfrac{x+1}{x-5}=\dfrac{0,5}{0,6};\\ \dfrac{2}{3}x:\dfrac{1}{5}=1\dfrac{1}{3}:\dfrac{1}{4};\\ 1,35:0,2=1,25:0,1x\)
1. tìm x |x| + x = 0 x + |x| = 2x x/|x| = -1 |3x-2| = x |x-2| = 2x + 1
2.tìm x , y, z thuộc Q |x +19/5| + | y + 1890/1975| + | z- 2004 | = 0 |x- 1/2| + | y+ 3/2 | + | x -y -z -1/2 | = 0
|15/32 - x | + |4/25 - y| + | z- 13/31| < 0
ve do thi y=3.x-4 ve 1 doan thang tu x=1 den x=3