Bài 1 : tìm x, biết
a) \(\left(\frac{1}{4}-x\right)\left(x+\frac{2}{5}\right)=0\)
bài 2 : Thực hiện các phép tính sau bằng cách hợp lí nếu có thể :
a) \(\left(\frac{13}{24}-\frac{29}{30}\right):\left(\frac{-51}{5}\right)\)
bài 3 : tính nhanh
A = \(\frac{1}{3}-\frac{3}{4}-\left(\frac{-3}{5}\right)+\frac{1}{72}-\frac{2}{9}-\frac{1}{36}+\frac{1}{15}\)
B = \(\frac{1}{5}-\frac{3}{7}+\frac{5}{9}-\frac{2}{11}+\frac{7}{13}-\frac{9}{16}-\frac{7}{13}+\frac{2}{11}-\frac{5}{9}+\frac{3}{7}-\frac{1}{5}\)
C = \(\frac{1}{100}-\frac{1}{100.99}-\frac{1}{99.98}-\frac{1}{98.97}-....-\frac{1}{3.2}-\frac{1}{2.1}\)
Bài 1: Thực hiện phép tính( bằng cahcs hợp lí nếu có thể)
\(a)\frac{7}{25}+\frac{4}{13}-\frac{5}{2}+\frac{18}{25}-1\frac{4}{13}\)
\(b)12-8.\left(\frac{3}{2}\right)^3\)
\(c)100\times\sqrt{0,04}+\sqrt{\frac{25}{16}}\)
\(d)\frac{1}{4}+\frac{3}{4}.\frac{5}{6}\)
\(e)3,75.7,2+2,8.3,75\)
\(f)\frac{1}{2}\sqrt{4}-\sqrt{25}\)
\(g)(\frac{1}{9})^{2005}.9^{2005}-96^2:24^2\)
\(h)\frac{15}{34}+\frac{7}{21}+\frac{19}{34}-\frac{20}{15}+\frac{3}{7}\)
\(k)\left(-3,5\right).\left(-7,2\right)+\left(-3,15\right).12,4+4,8.\left(-3,15\right)\)
\(l)16\frac{2}{7}:\left(-\frac{2}{5}\right)-28\frac{2}{7}:\left(-\frac{2}{5}\right)\)
\(m)\left(-\frac{1}{2}\right)^3+\frac{1}{2}:5\)
\(n)1\frac{1}{23}+\frac{2}{21}-\frac{1}{23}+\frac{19}{21}+2013^0\)
\(h)\frac{-5}{9}.\left(\frac{3}{10}-\frac{2}{5}\right)\)
\(i)\frac{1}{2}\sqrt{64}-\sqrt{\frac{4}{25}+1^{2012}}\)
Giải Hộ Mk vs Mk đng cần gấp để nộp
HELP MEEEEEEEEEEEEEEEEEEEE
Câu 1: Thực hiện phép tính bằng cách hợp lí
\(\frac{15}{35}+\frac{7}{21}+\frac{19}{34}-1\frac{15}{17}+\frac{2}{3}\)
\(\left(-2\right)^3.\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
\(16\frac{2}{7}:\left(-\frac{3}{5}\right)+28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Câu 2: Tìm x biết
\(2.x-\frac{5}{4}=\frac{20}{15}\)
\(1,5:0,3=x:-15\)
\(|2x-1|=2\)
Câu 3: Thực hiện phép tính hợp lí
\(\frac{11}{12}.\frac{15}{33}+\frac{11}{12}.\frac{2}{22}\)
\(3/3\frac{1}{8}.11\frac{17}{19}-3\frac{1}{8}.13\frac{17}{19}\)
\(28\frac{2}{7}:\left(-\frac{3}{5}\right)+16\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Giúp mình làm bài này trước 8h
Bài 1 : Thực hiện phép tính(nếu có thể )
a)\(\left(31\frac{6}{13}+5\frac{9}{41}\right)-36\frac{6}{13}\)
b) \(\frac{5}{3}+\left(\frac{-2}{7}\right)-\left(-1,2\right)-\left|1,4-0,2\right|\)
c) \(0,25+\frac{3}{5}-\left(\frac{1}{8}-\frac{2}{5}+1\frac{1}{4}\right)+\left|-\frac{3}{5}\right|\)
Bài 2 : Tìm x, biết
a) \(-\frac{3}{5}-x=0,75\)
b)\(x+\frac{1}{3}=\frac{2}{5}-\left(-\frac{1}{3}\right)\)
c)\(\left|2x-4\right|+1=5\)
TÌm số hữu tỉ x trong tỉ lệ thức:
a) 0,4 : x = x : 0,9
b) \(13\frac{1}{3}:1\frac{1}{3}=26:\left(2x-1\right)\)
c) \(0,2:1\frac{1}{5}=\frac{2}{3}:\left(6x+7\right)\)
d) \(\frac{37-x}{x+13}=\frac{3}{7}\)
thực hiện phép tính (tính nhanh nếu có thể) :
a)\(1\frac{3}{19}+\frac{8}{21}-\frac{3}{19}+0.5+\frac{13}{21}\)
b)\(\left(-\frac{3}{4}+\frac{2}{7}\right):\frac{3}{7}+\left(\frac{5}{7}+\frac{-1}{4}\right):\frac{3}{7}\)
c)\(\left(\frac{1}{6}\right)^7\times6\)
d)\(\left(\frac{-1}{2}\right)^3+\frac{1}{2}:3\)
Bài 1 tìm x biết x=\(\frac{2}{3}.S\)
S=\(\frac{\left(9\frac{3}{8}:5.2+3,4.2\frac{7}{34}\right):1\frac{9}{16}}{0,31.8\frac{2}{5}-5,61:27\frac{1}{3}}\)
Tìm 15% của M biết
M=\(\frac{\left(23\frac{11}{15}-26\frac{13}{20}\right)}{12^2+5^2}:\frac{1-\frac{1}{3}-\frac{1}{42}-\frac{1}{56}}{3^2.13.2}-\frac{19}{37}\)
Tính giá trị biểu thức
\(1.A=\frac{1}{5}+\frac{3}{17}-\frac{4}{3}+\left(\frac{4}{5}-\frac{3}{17}+\frac{1}{3}\right)-\frac{1}{7}+\left[\frac{-14}{30}\right]\)
\(2.B=\left(\frac{5}{8}-\frac{4}{12}+\frac{3}{2}\right)-\left(\frac{5}{8}+\frac{9}{13}\right)-\left[\frac{-3}{2}\right]+\frac{7}{-15}\)
\(3.C=\frac{5}{18}+\frac{8}{19}-\frac{7}{21}+\left(\frac{-10}{36}+\frac{11}{19}+\frac{1}{3}\right)-\frac{5}{8}\)
\(4.D=\frac{1}{9}-\left[\frac{-5}{23}\right]-\left(\frac{-5}{23}+\frac{1}{9}+\frac{25}{7}\right)+\frac{50}{14}-\frac{7}{30}\)
\(5.E=\frac{1}{13}+\left(\frac{-5}{18}-\frac{1}{13}+\frac{12}{17}\right)+\left(\frac{12}{17}+\frac{5}{18}+\frac{7}{5}\right)\)
\(6.F=\frac{15}{14}-\left(\frac{17}{23}-\frac{80}{87}+\frac{5}{4}\right)+\left(\frac{12}{17}-\frac{15}{14}+\frac{1}{4}\right)\)
\(7.G=\frac{1}{25}-\frac{4}{27}+\left(\frac{-23}{27}+\frac{-1}{25}-\frac{5}{43}\right)+\frac{5}{43}-\frac{4}{7}\)
\(8.H=\frac{4}{15}-\frac{23}{28}-\left(\frac{-23}{28}+\frac{-11}{15}-\frac{29}{27}\right)-\frac{2}{27}\)
\(9.K=\frac{1}{16}-\frac{5}{21}+\left(\frac{-1}{16}+\frac{-3}{5}-\frac{-5}{21}\right)+\frac{-2}{5}+\frac{3}{4}\)
\(10.L=\frac{7}{12}+\frac{15}{14}-\left(\frac{14}{22}+\frac{-1}{14}+\frac{5}{21}\right)-\frac{-5}{21}+\frac{3}{5}\)
tìm x biết:
A) \(\frac{7}{\left(x+3\right)\left(x+10\right)}\)\(+\frac{11}{\left(x+10\right)\left(x+21\right)}+\frac{13}{\left(x+21\right)\left(x+34\right)}=\frac{x}{\left(x+3\right)\left(x+34\right)}\)
B)\(\frac{3}{\left(x-4\right)\left(x-7\right)}+\frac{6}{\left(x-7\right)\left(x-13\right)}+\frac{15}{\left(x-13\right)\left(x-28\right)}-\frac{1}{x-28}=-\frac{5}{2}\)