\(\dfrac{2^7.3+2^{10}}{13.2^7-14.2^6}\)
\(\dfrac{8^{14}}{4^4.64^5}\)
\(\dfrac{9^{10}.27^7}{81^7.3^{15}}\)
\(\left(\dfrac{3}{10}\right)^4.\left(0,3\right)^5.\left(\dfrac{10}{3}\right)^{10}\)
\(\dfrac{\left(4^3\right)^2.9^4}{6^7.8^2}\)
\(\dfrac{4^8.9^4}{6^6.8^3}\)
\(3^6.\left(\dfrac{1}{3}\right)^6.81^2.\dfrac{1}{27^2}\) TÍNH
\(\dfrac{8^{14}}{4^4.64^5}=\dfrac{\left(2^3\right)^{14}}{\left(2^2\right)^4.\left(2^5\right)^5}=\dfrac{2^{42}}{2^8.2^{25}}=2^{42-\left(8+25\right)}=2^9\)
\(\dfrac{9^{10}.27^7}{81^7.3^{15}}=\dfrac{\left(3^2\right)^{10}.\left(3^3\right)^7}{\left(3^4\right)^7.3^{15}}=\dfrac{3^{20}.3^{21}}{3^{28}.3^{15}}=\dfrac{3^{20+21}}{3^{28+15}}=\dfrac{3^{41}}{3^{41}.3^2}=\dfrac{1}{3^2}=\dfrac{1}{9}\)
Rút gọn các phân số sau:
a)\(\dfrac{11.8-11.3}{17-6}\) ; b)\(\dfrac{24-12.13}{12+4.9}\); c)\(\dfrac{7.6-7.4}{7.3}\); d)\(\dfrac{7}{9.10^2-2.10^2}\)
a) \(\dfrac{11\cdot8-11\cdot3}{17-6}\)
\(=\dfrac{11\cdot\left(8-3\right)}{11}=5\)
b) \(\dfrac{24-12\cdot13}{12+4\cdot9}\)
\(=\dfrac{12\cdot\left(2-13\right)}{12\left(1+3\right)}=\dfrac{-11}{4}\)
Rút gọn các phân số sau:
a)\(\dfrac{13.9-13.2}{25-12}\) b) \(\dfrac{42-14.8}{7+21.3}\)
c)\(\dfrac{9.6-18.4}{12.3}\)
d)\(\dfrac{5.5^2}{9.10^2-4.10^2}\)
a: \(=\dfrac{13\cdot\left(9-2\right)}{13}=7\)
b: \(=\dfrac{14\left(3-8\right)}{7\left(1+3\cdot3\right)}=2\cdot\dfrac{-5}{10}=-1\)
c: \(=\dfrac{54-72}{36}=\dfrac{-18}{36}=-\dfrac{1}{2}\)
d: \(=\dfrac{5^3}{10^2\cdot5}=\dfrac{5^2}{100}=\dfrac{1}{4}\)
Câu 1: Rút gọn các biểu thức sau:
C = \(\dfrac{8^2.9^5}{3^9.4^3}\)
D = \(\dfrac{81^6.9^5}{27^7.3^{11}}\)
F = \(\dfrac{8^{15}.25^7}{125^5.2^{47}}\)
G = \(\dfrac{10^2.5^3}{8.25^2}\)
\(C=\dfrac{2^6\cdot3^{10}}{3^9\cdot2^6}=3\\ D=\dfrac{3^{24}\cdot3^{10}}{3^{21}\cdot3^{11}}=\dfrac{3^{34}}{3^{32}}=3^2=9\\ F=\dfrac{2^{45}\cdot5^{14}}{5^{15}\cdot2^{47}}=\dfrac{1}{2^2\cdot5}=\dfrac{1}{20}\\ G=\dfrac{2^2\cdot5^2\cdot5^3}{2^3\cdot5^4}=\dfrac{1\cdot5}{2}=\dfrac{5}{2}\)
C=3
D=9
F=1/20
G=5/2
Em ko giải chi tiết vì nó lâu
Mong thông cảm!
C= \(\dfrac{8^2.9^5}{3^9.4^3}\)
= \(\dfrac{\left(2^3\right)^2.\left(3^2\right)^5}{3^9.\left(2^2\right)^3}\)
= \(\dfrac{2^6.3^{10}}{3^9.2^6}\)
= \(\dfrac{3^1}{1}\)
= \(\dfrac{3}{1}\)
Thực hiện phép tính :
1) A = \(\dfrac{155-\dfrac{10}{7}-\dfrac{5}{11}+\dfrac{5}{23}}{403-\dfrac{26}{7}-\dfrac{13}{11}+\dfrac{13}{23}}+\dfrac{\dfrac{3}{5}+\dfrac{3}{13}-0,9}{\dfrac{7}{91}+0,2-\dfrac{3}{10}}\)
2) B = \(\dfrac{30.4^7.3^{29}-5.14^5.2^{12}}{54.6^{14}.9^7-12.8^5.7^5}\)
1: \(A=\dfrac{5\left(31-\dfrac{2}{7}-\dfrac{1}{11}+\dfrac{1}{23}\right)}{13\left(31-\dfrac{2}{7}-\dfrac{1}{11}+\dfrac{1}{23}\right)}+\dfrac{3\left(\dfrac{1}{5}+\dfrac{1}{13}-\dfrac{3}{10}\right)}{\dfrac{1}{13}+\dfrac{1}{5}-\dfrac{3}{10}}\)
=5/13+3
=5/13+39/13
=44/13
2: \(B=\dfrac{2^{15}\cdot3^{30}\cdot5-5\cdot2^5\cdot7^5\cdot2^{12}}{3^3\cdot2\cdot2^{14}\cdot3^{14}\cdot3^{14}-2^2\cdot3\cdot2^{15}\cdot7^5}\)
\(=\dfrac{5\cdot2^{15}\left(3^{30}-2^2\cdot7^5\right)}{3^{31}\cdot2^{15}-2^{17}\cdot3\cdot7^5}\)
\(=\dfrac{5\cdot2^{15}\left(3^{30}-2^2\cdot7^5\right)}{3\cdot2^{15}\cdot\left(3^{30}-2^2\cdot7^5\right)}=\dfrac{5}{3}\)
thực hiện phép tính; \(\dfrac{2^{18}.18^7.3^3+3^{15}.2^{15}}{2^{10}.6^{15}+3^{14}.15.4^3}\)
\(=\dfrac{2^{18}\cdot3^3\cdot\left(3^2\cdot2\right)^7+3^{15}\cdot2^{15}}{2^{10}\cdot2^{15}\cdot3^{15}+3^{14}\cdot3\cdot5\cdot2^6}\)
\(=\dfrac{2^{25}\cdot3^{17}+3^{15}\cdot2^{15}}{2^{25}\cdot3^{15}+3^{15}\cdot5\cdot2^6}\)
\(=\dfrac{2^{15}\cdot3^{15}\left(2^{10}\cdot3^2+1\right)}{2^6\cdot3^{15}\left(2^{19}+5\cdot1\right)}=\dfrac{2^9\cdot9217}{524293}\)
1. tìm x
a, 2x - \(\dfrac{1}{2}\) : \(\dfrac{3}{4}\) = \(\dfrac{12}{9}\)
b, x\(^2\) - 2 = 0
2. Cho
A = \(\dfrac{1,11+0,19-13.2}{2,06+0,54}\) - \(\left(\dfrac{1}{2}+\dfrac{1}{4}\right)\) : 2
B = \(\left(5\dfrac{7}{8}-2\dfrac{1}{4}-0,5\right)\) : \(2\dfrac{23}{26}\)
a, Rút gọn A, B
b, Tìm x ϵ Z để A < x < B
a)
=\(2x-\dfrac{1}{2}=\dfrac{12}{9}\cdot\dfrac{3}{4}=1\)
=\(2x=1+\dfrac{1}{2}=1.5\)
=\(x=1.5:2=0.75\)
b)
=\(x^2=0+2=2\)
TH1:\(x=2\)
TH2:\(x=-2\)
Bài 1:
a: \(2x-\dfrac{1}{2}:\dfrac{3}{4}=\dfrac{12}{9}\)
=>\(2x-\dfrac{1}{2}\cdot\dfrac{4}{3}=\dfrac{4}{3}\)
=>\(2x=\dfrac{4}{3}+\dfrac{2}{3}=\dfrac{6}{3}=2\)
=>x=2/2=1
b: \(x^2-2=0\)
=>\(x^2=2\)
=>\(\left[{}\begin{matrix}x=\sqrt{2}\\x=-\sqrt{2}\end{matrix}\right.\)
Bài 2:
a: \(A=\dfrac{1,11+0,19-13\cdot2}{2,06+0,54}-\left(\dfrac{1}{2}+\dfrac{1}{4}\right):2\)
\(=\dfrac{1,3-26}{2,6}-\dfrac{3}{4}:2\)
\(=-9,5-\dfrac{3}{8}=-\dfrac{79}{8}\)
\(B=\left(5\dfrac{7}{8}-2\dfrac{1}{4}-0,5\right):\left(2\dfrac{23}{26}\right)\)
\(=\left(5+\dfrac{7}{8}-2-\dfrac{1}{4}-\dfrac{1}{2}\right):\dfrac{75}{26}\)
\(=\left(3+\dfrac{1}{8}\right)\cdot\dfrac{26}{75}=\dfrac{25}{8}\cdot\dfrac{26}{75}=\dfrac{13}{12}\)
b: A<x<B
=>\(-\dfrac{79}{8}< x< \dfrac{13}{12}\)
mà \(x\in Z\)
nên \(x\in\left\{-9;-8;...;0;1\right\}\)
Tính giá trị biểu thức sau:
\(\dfrac{2^7.3^8}{6^6}\)
\(\dfrac{2^7\cdot3^8}{6^6}\)
\(=\dfrac{2^7\cdot3^8}{2^6\cdot3^6}\)
\(=2\cdot3^2\)
\(=2\cdot9\)
\(=18\)
\(\dfrac{7.12^8.5^4-6^9.20^4}{6^{10}.10^5-7.3^9.80^4}\)