giúp mk vs làm mãi ko ra mk cảm ơn trc.
a)\(P=\dfrac{\dfrac{42}{31}.\dfrac{31}{7}-\left(1.5-6\dfrac{1}{3}.\dfrac{2}{19}\right)}{4\dfrac{5}{6}+\dfrac{1}{6}.\left(12-5\dfrac{1}{3}\right)}.\left(-1:\dfrac{14}{39}\right)\)
b)\(Q=\left(\dfrac{1}{4}-1\right).\left(\dfrac{1}{9}-1\right).\left(\dfrac{1}{16}-1\right).\left(\dfrac{1}{25}-1\right).....\left(\dfrac{1}{121}-1\right)\)
Câu 1: Tinh
\(A=\left(\dfrac{3}{5}\right)^2.5^2-\left(2\dfrac{1}{4}\right)^3:\left(\dfrac{3}{4}\right)^3+\dfrac{1}{2}\)
\(B=\left[\dfrac{4}{11}.\left(\dfrac{1}{25}\right)^0+\dfrac{7}{22}.2\right]^{2010}-\left(\dfrac{1}{2^2}:\dfrac{8^2}{4^4}\right)^{2009}\)
\(\dfrac{7}{8}.\left(\dfrac{2}{12}+\dfrac{4}{10}\right)\)
\(\dfrac{3}{2}-\dfrac{5}{6}:\left(\dfrac{1}{2}\right)^2+\sqrt{4}\)
Câu 2: Tim x
\(2.x-\dfrac{5}{4}=\dfrac{20}{15}\)
\(\left(x+\dfrac{1}{3}\right)^3=\left(\dfrac{-1}{8}\right)\)
E=\(\dfrac{98:\left(\dfrac{4}{5}.1,25\right)}{0,64-\dfrac{1}{25}}\) + \(\dfrac{\left(1.08-\dfrac{2}{25}\right):\dfrac{4}{7}}{\left(6\dfrac{5}{9}-3\dfrac{1}{4}\right).2\dfrac{2}{17}}\)
mọi người ơi giúp mình bài này vơi , ai làm đc mik tick cho
1. Tính ( hợp lý nếu có thể )
a, A = \(\dfrac{7,5-0,6+\dfrac{3}{7}+\dfrac{3}{13}}{2,75-2,2+\dfrac{11}{7}+\dfrac{11}{3}}\)
b, B = 26 : \(\left[\dfrac{3:\left(0,2-0,1\right)}{2,5.\left(0,8+1,2\right)}+\dfrac{\left(34,06-33,81\right).4}{6.84:\left(28,57-25,15\right)}\right]\)+ \(\dfrac{2}{3}\) : \(\dfrac{4}{21}\)
c, C = \(\left[\left(\dfrac{2}{193}-\dfrac{3}{386}\right).\dfrac{193}{17}+\dfrac{33}{34}\right]\) : \(\left[\left(\dfrac{7}{2001}+\dfrac{11}{4002}\right).\dfrac{2001}{25}+\dfrac{9}{2}\right]\)
d, D = \(\dfrac{0.8:\left(\dfrac{4}{5}.1,25\right)}{0.64-\dfrac{1}{25}}\) + \(\dfrac{\left(1.08-\dfrac{5}{25}\right):\dfrac{4}{7}}{\left(6\dfrac{5}{9}-3\dfrac{1}{4}\right).2\dfrac{2}{7}}\) + ( 11,2 . 0,5 ) : \(\dfrac{4}{5}\)
Giúp mk nha chỉ là tính toán thông thường tính ra là đc nhưng mà mk lại khó tính ra nên các bn giúp mk nha
a) \(\left[\left(-32,47\right)+68,12\right]+32,47\)
b) \(\left[\left(-61,8\right)+\left(-123,6\right)\right]+\left[83,6+61,8\right]\)
c) \(-\left(\dfrac{2}{7}+\dfrac{1}{3}-\dfrac{5}{6}\right)-\left(\dfrac{-9}{7}+\dfrac{14}{7}-\dfrac{1}{5}+\dfrac{5}{3}\right)\)
Tìm x biết :
a )\(\left|2x-1\right|=1,5\)
b)\(7,5-\left|5-2x\right|=-4,5\)
c)\(-3+\left|x\right|=-1\)
d)\(\left|2\dfrac{1}{3}-x\right|=\dfrac{1}{6}\)
e)\(\dfrac{5}{7}-\left|x+1\right|=\dfrac{1}{14}\)
f)\(\left|2x+3\dfrac{1}{5}\right|-\dfrac{1}{2}=\dfrac{3}{10}\)
Cho biểu thức \(A=\dfrac{1}{3}+\left(\dfrac{1}{3}\right)^2+\left(\dfrac{1}{3}\right)^3+...+\left(\dfrac{1}{3}\right)^{2019}+\left(\dfrac{1}{3}\right)^{2020}\). Chứng minh rằng A \(< \dfrac{1}{2}\)
Giúp mk đi, 23h là mk phải nộp rùi
Tìm x:
a) \(\left|x+1,2\right|=0,5\)
b) \(\left|x-\dfrac{1}{2}\right|+\dfrac{5}{6}=1\dfrac{1}{2}\)
c) \(\left|x-\dfrac{1}{2}\right|+\dfrac{4}{5}=\left|\left(-3,2\right)+\dfrac{2}{5}\right|\)
Tìm x biết:
a) \(\left|x-\dfrac{1}{2}\right|+\left|x+2\right|=\dfrac{3}{4}\)
b) \(\left(\dfrac{2}{3}-2x\right).1\dfrac{1}{2}=\dfrac{3}{4}\)
c) \(\left|x-1\right|+2\left(x+4\right)=10\)
d) \(\dfrac{11}{12}+\dfrac{11}{12.23}+...+\dfrac{11}{89.100}+x=1\dfrac{2}{3}\)
e) \(\left(\dfrac{2}{11.13}+\dfrac{2}{13.15}+...+\dfrac{2}{19.21}\right)-x+4\dfrac{221}{231}=2\dfrac{1}{3}\)
Bài 4 : Tìm x,y biết :
a)\(3\dfrac{1}{4}-\dfrac{1}{4}\left|x-0,25\right|=\dfrac{1}{4}\)
b)\(\left|x-3\right|=-4\)
c)\(\left|x-\dfrac{1}{2}\right|+1=0\)
d)\(\left|x-\dfrac{1}{5}\right|=\left|\dfrac{3}{4}-2x\right|\)
e)\(\left|x+2\right|3=0\)
f)\(\left|2x-1\right|-\left|x+2\right|=0\)
g)\(\left|x+2\right|+\left|y-1\right|=0\)
h)\(\left|2x\right|+\left|y+\dfrac{1}{4}\right|=0\)
