Bài 1: Tính ( Nhanh nếu có thể )
a) \(25.8^3-23.8^3\)
b) \(5^4-2.5^3\)
c) \(2.4^3-4^3.7-6.4^3\)
d) \(3^2.10^3-\left[13^2-\left(5^2.4+2^2.15\right)\right]\)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(25.8^3-23.8^3=8^3\left(25-23\right)\)
\(=8^3.2\)
\(=2^9.2=2^{10}\)
b) \(5^4-2.5^3=5^3.5-2.5^3\)
\(=5^3\left(5-2\right)\)
\(=5^3.3=375\)
c)\(2.4^3-4^3.7-6.4^3=4^3\left(2-7-6\right)\)
\(=4^3.-11=-704\)
d)\(3^2.10^3-\left[13^2-\left(5^2.4+2^2.15\right)\right].10^3\)
\(=3^2.10^3-\left[13^2-2^2\left(5^2+15\right)\right].10^3\)
\(=3^2.10^3-\left[13^2-2^2.40\right].10^3\)
\(=10^3\left[3^2-9\right]\)
\(=0\)
\(1,\\ a,=\left(\dfrac{1}{4}\right)^3\cdot32=\dfrac{1}{64}\cdot32=\dfrac{1}{2}\\ b,=\left(\dfrac{1}{8}\right)^3\cdot512=\dfrac{1}{512}\cdot512=1\\ c,=\dfrac{2^6\cdot2^{10}}{2^{20}}=\dfrac{1}{2^4}=\dfrac{1}{16}\\ d,=\dfrac{3^{44}\cdot3^{17}}{3^{30}\cdot3^{30}}=3\\ 2,\\ a,A=\left|x-\dfrac{3}{4}\right|\ge0\\ A_{min}=0\Leftrightarrow x=\dfrac{3}{4}\\ b,B=1,5+\left|2-x\right|\ge1,5\\ A_{min}=1,5\Leftrightarrow x=2\\ c,A=\left|2x-\dfrac{1}{3}\right|+107\ge107\\ A_{min}=107\Leftrightarrow2x=\dfrac{1}{3}\Leftrightarrow x=\dfrac{1}{6}\)
\(d,M=5\left|1-4x\right|-1\ge-1\\ M_{min}=-1\Leftrightarrow4x=1\Leftrightarrow x=\dfrac{1}{4}\\ 3,\\ a,C=-\left|x-2\right|\le0\\ C_{max}=0\Leftrightarrow x=2\\ b,D=1-\left|2x-3\right|\le1\\ D_{max}=1\Leftrightarrow x=\dfrac{3}{2}\\ c,D=-\left|x+\dfrac{5}{2}\right|\le0\\ D_{max}=0\Leftrightarrow x=-\dfrac{5}{2}\)
a,32
b,\(-\frac{1}{10}\)
c,-1000000
d,\(\frac{9}{16}\)
Bài 1 :
a) \(25.8^3-23.8^3\)
\(=8^3.\left(25-23\right)\)
\(=512.2=1024\)
b) \(5^4-2.5^3\)
\(=5^3.5-2.5^3\)
\(=5^3\left(5-2\right)\)
\(=125.3\)
\(=375\)
c) \(2.4^3-4^3.7-6.4^3\)
\(=4^3.\left(2-7-6\right)\)
\(=64.\left(-11\right)=-704\)
d) \(3^2.10^3-\left[13^2-\left(5^2.4+2^2.15\right)\right]\)
\(=9.1000-\left[169-\left(25.4+4.15\right)\right]\)
\(=9000-\left[169-4\left(25+15\right)\right]\)
\(=9000-\left[169-4.40\right]\)
\(=9000-\left[169-160\right]\)
\(=9000-9=8991\)
o0o Ma Kết _ Capricorn o0o trời ơi là trời, thể nào mk thấy nó là lạ!
\(3^2.10^3-\left[13^2\left(5^2.4+2^2.15\right)\right].10^3\)
\(=9.1000-\left[169\left(25.4+4.15\right)\right].1000\)
\(=9000-\left\{169.\left[4\left(25+15\right)\right]\right\}.1000\)
\(=9000-\left\{169.\left[4.40\right]\right\}.1000\)
\(=9000-\left\{169.160\right\}.1000\)
Tự tính tiếp nhé!!