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Tìm x,y,za)frac{x}{4}-frac{1}{9}frac{1}{2}left(xthuộcZright)b)x+yxyx:yleft(vớiright)xykhác0c)x-yxyxyleft(ykhac0right)d)left(x+1right)left(x-2right) 0e)left(x-2right)left(x+frac{2}{3}right)0f)xleft(x+y+zright)-5yleft(x+y+zright)9zleft(x+y+zright)5
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Tìm x,y,z
a)\(\frac{x}{4}-\frac{1}{9}=\frac{1}{2}\left(xthuộcZ\right)\)
b)\(x+y=xy=x:y\left(với\right)xykhác0\)
c)\(x-y=xy=xy\left(ykhac0\right)\)
d)\(\left(x+1\right)\left(x-2\right)< 0\)
e)\(\left(x-2\right)\left(x+\frac{2}{3}\right)>0\)
f)\(x\left(x+y+z\right)=-5\)
\(y\left(x+y+z\right)=9\)
\(z\left(x+y+z\right)=5\)
rút gona,frac{2.5^{22}-9.5^{21}}{25^{10}}b,frac{5left(3.7^{15}-19.7^{14}right)}{7^{16}+3.7^{15}}c,frac{left(left(-2right)^2right)^3.left(-4right)^2}{left(-2right)^3.left(-2right)^2} d,frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}e,2^3+3.left(frac{1}{8}right)^0-left(frac{1}{2^2}right).4+left[left(-2right)^2:frac{1}{2}right].8f,frac{left(frac{2}{5}right)^7.5^5+left(frac{9}{4}right)^3:left(frac{3}{16}right)^3}{2^7.5^2+512}
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rút gon
a,\(\frac{2.5^{22}-9.5^{21}}{25^{10}}\)
b,\(\frac{5\left(3.7^{15}-19.7^{14}\right)}{7^{16}+3.7^{15}}\)
c,\(\frac{\left(\left(-2\right)^2\right)^3.\left(-4\right)^2}{\left(-2\right)^3.\left(-2\right)^2}\)
d,\(\frac{4^6.9^5+6^9.120}{8^4.3^{12}-6^{11}}\)
e,\(2^3+3.\left(\frac{1}{8}\right)^0-\left(\frac{1}{2^2}\right).4+\left[\left(-2\right)^2:\frac{1}{2}\right].8\)
f,\(\frac{\left(\frac{2}{5}\right)^7.5^5+\left(\frac{9}{4}\right)^3:\left(\frac{3}{16}\right)^3}{2^7.5^2+512}\)
1 tìm x,y biết\(a,\left|3x-\frac{1}{2}\right|+\left|\frac{1}{2}y+\frac{3}{5}\right|=0\)
Xem chi tiết
\(b.\left|\frac{3}{2}x+\frac{1}{9}\right|+\left|\frac{1}{5}y-\frac{1}{2}\right|\le0\)
a, A= \(\left(15x+2y\right)-\left[\left(2x+3\right)-\left(5x+y\right)\right]\) tại x=1 ; y= -1
b, B= -\(\left(12x+3y\right)+\left(5x-2y\right)-\left[13x+\left(2y+5\right)\right]\) tại x= \(\frac{-1}{2}\); y= \(\frac{1}{7}\)
M= 1+\(\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+.......+\frac{1}{16}\left(1+2+3+...+16\right)\)
Tính M
a) Tìm x,y,z biết : \(\frac{x}{y+z+1}=\frac{y}{x+z+1}=\frac{z}{x+y-2}=x+y+z\)
b) Tìm x biết : \(\left|x\right|+\left|x-1\right|+\left|x-2\right|=6\)
Thực hiện phép tínha)16frac{2}{7}:left(frac{-3}{5}right)+28frac{2}{7}:frac{3}{5}b)left(2^2:frac{4}{3}-frac{1}{2}right).frac{6}{5}-17c)left(frac{1}{3}right)^{50}.left(-9right)^{25}-frac{2}{3}:4d)frac{3}{5}:left(frac{-1}{15}-frac{1}{6}right)+frac{3}{5}:left(frac{-1}{3}-1frac{1}{15}right)e)left(-6,5right).5,7+5,7.left(-3,5right)
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Thực hiện phép tính
a)\(16\frac{2}{7}:\left(\frac{-3}{5}\right)+28\frac{2}{7}:\frac{3}{5}\)
b)\(\left(2^2:\frac{4}{3}-\frac{1}{2}\right).\frac{6}{5}-17\)
c)\(\left(\frac{1}{3}\right)^{50}.\left(-9\right)^{25}-\frac{2}{3}:4\)
d)\(\frac{3}{5}:\left(\frac{-1}{15}-\frac{1}{6}\right)+\frac{3}{5}:\left(\frac{-1}{3}-1\frac{1}{15}\right)\)
e)\(\left(-6,5\right).5,7+5,7.\left(-3,5\right)\)
a ) Tính A = \(\left(\frac{1}{2^2}-1\right)\left(\frac{1}{3^2}-1\right)\left(\frac{1}{4^2}-1\right)...\left(\frac{1}{100^2}-1\right)\)
b ) Tìm x và y biết : x , y \(\in\) Z và 2x + 2y = 2x+y
a ) Tính : \(\left(1-\frac{2}{5}\right)\left(1-\frac{2}{7}\right)\left(1-\frac{2}{9}\right)...\left(1-\frac{2}{99}\right)\)
b ) Cho 2x = 8y+1 và 9y = 3x-9 . Tính x + y