(180:15-1332:11)x(57869-297:11x108)
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1.
\(\left(572\cdot7+266\right)\cdot\left(366\cdot9-168\cdot18\right)\cdot\left(346\cdot6-348\right)\)
\(=\left(286\cdot7\cdot2+133\cdot2\right)\cdot\left(366\cdot9-168\cdot2\cdot9\right)\cdot\left(173\cdot6\cdot2-174\cdot2\right)\)
\(=\left(2002\cdot2+133\cdot2\right)\cdot\left(366\cdot9-336\cdot9\right)\cdot\left(1038\cdot2-174\cdot2\right)\)
\(=\left[2\cdot\left(2002+133\right)\right]\cdot\left[9\cdot\left(366-336\right)\right]\cdot\left[2\cdot\left(1038-174\right)\right]\)
\(=2\cdot2135\cdot9\cdot30\cdot2\cdot864\)
\(=4270\cdot9\cdot30\cdot2\cdot864\)
\(=\left(4270\cdot30\right)\cdot9\cdot2\cdot864\)
\(=\left(427\cdot10\right)\cdot\left(3\cdot10\right)\cdot9\cdot2\cdot864\)
\(=\left(427\cdot3\right)\cdot\left(10\cdot10\right)\cdot9\cdot2\cdot864\)
\(=1281\cdot100\cdot9\cdot2\cdot864\)
\(=\left(1281\cdot100\right)\cdot\left(9\cdot2\cdot864\right)\)
\(=\left(1281\cdot100\right)\cdot15552\)
\(=\left(1281\cdot15552\right)\cdot100\)
\(=19922112\cdot100\)
\(=1992211200\)
2.
\(\left(1+3+5+7+...+97+9\right)\cdot\left(45\cdot3-15\cdot2-45\right)\)
\(=\left(1+3+5+7+...+97+9\right)\cdot\left(15\cdot3\cdot3-15\cdot2-15\cdot3\right)\)
\(=\left(1+3+5+7+...+97+9\right)\cdot\left[15\cdot\left(3\cdot3\right)-15\cdot2-15\cdot3\right]\)
\(=\left(1+3+5+7+...+97+9\right)\cdot\left(15\cdot9-15\cdot2-15\cdot3\right)\)
\(=\left(1+3+5+7+...+97+9\right)\cdot\left[15\cdot\left(9-2-3\right)\right]\)
\(=\left(1+3+5+7+...+97+9\right)\cdot15\cdot4\)
\(=\left[\left(1+3+5+7+...+97\right)+9\right]\cdot\left(15\cdot4\right)\)
Trong \(\left(1+3+5+7+...+97\right)\) có số số hạng là:
\(\left(97-1\right)\div2+1=49\) ( số hạng )
\(\Rightarrow\left[\left(1+3+5+7+...+97\right)+9\right]\cdot\left(15\cdot4\right)\)
\(=\left[\left(97+1\right)\cdot49\div2\right]\cdot\left(15\cdot4\right)\)
\(=2401\cdot60\)
\(=\left(2401\cdot6\right)\cdot10\)
\(=14406\cdot10\)
\(=144060\)
3.
\(\left(180\div15-132\div11\right)\cdot\left(57869-297\div11\cdot108\right)\)
\(=\left(12-12\right)\cdot\left(57869-297\div11\cdot108\right)\)
\(=0\cdot\left(57869-297\div11\cdot108\right)\)
\(=0\)
Sửa lại bài 2; dòng 11 ( từ đề bài bài 2 ):
\(=\left\{\left[\left(97+1\right)\cdot49\div2\right]+9\right\}\cdot\left(15\cdot4\right)\)
\(=\left(2401+9\right)\cdot\left(15\cdot4\right)\)
\(=2410\cdot\left(15\cdot4\right)\)
\(=2410\cdot60\)
\(=\left(241\cdot10\right)\cdot\left(6\cdot10\right)\)
\(=\left(241\cdot6\right)\cdot\left(10\cdot10\right)\)
\(=1446\cdot10\)
\(=14460\)
1) \(\left(x-2\right)\left(x+4\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x-2=0\\x+4=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=2\\x=-4\end{matrix}\right.\)
2) \(\left(x-2\right)\left(x+15\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x-2=0\\x+15=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=2\\x=-15\end{matrix}\right.\)
3) \(\left(7-x\right)\left(x+19\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}7-x=0\\x+19=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=7\\x=-19\end{matrix}\right.\)
4) \(-5< x< 1\)
\(\Rightarrow x\in\left\{-1;-3;-2;-1;0\right\}\)
5) \(\left(x-3\right)\left(x-5\right)< 0\)
\(\Rightarrow\left[{}\begin{matrix}x-3>0\\x-5< 0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x>3\\x< 5\end{matrix}\right.\)
\(\Rightarrow3< x< 5\)
6) \(2x^2-3=29\)
\(\Rightarrow2x^2=29+3\)
\(\Rightarrow2x^2=32\)
\(\Rightarrow x^2=\dfrac{32}{2}\)
\(\Rightarrow x^2=16\)
\(\Rightarrow x^2=4^2\)
\(\Rightarrow\left[{}\begin{matrix}x=4\\x=-4\end{matrix}\right.\)
7) \(-6x-\left(-7\right)=25\)
\(\Rightarrow-6x+7=25\)
\(\Rightarrow-6x=25-7\)
\(\Rightarrow-6x=18\)
\(\Rightarrow x=\dfrac{18}{-6}\)
\(\Rightarrow x=-3\)
8) \(46-\left(x-11\right)=-48\)
\(\Rightarrow x-11=48+46\)
\(\Rightarrow x-11=94\)
\(\Rightarrow x=94+11\)
\(\Rightarrow x=105\)
1: (x-2)(x+4)=0
=>x-2=0 hoặc x+4=0
=>x=2 hoặc x=-4
2: (x-2)(x+15)=0
=>x-2=0 hoặc x+15=0
=>x=2 hoặc x=-15
3: (7-x)(x+19)=0
=>7-x=0 hoặc x+19=0
=>x=7 hoặc x=-19
4: -5<x<1
=>\(x\in\left\{-4;-3;-2;-1;0\right\}\)
5: (x-3)(x-5)<0
=>x-3>0 và x-5<0
=>3<x<5
6: 2x^2-3=29
=>2x^2=32
=>x^2=16
=>x=4 hoặc x=-4
7: -6x-(-7)=25
=>-6x=25-7=18
=>x=-3
8: 46-(x-11)=-48
=>x-11=46+48=94
=>x=94+11=105
\(=\left(1+3-5-7\right)+\left(9+11-13-15\right)+...+\left(297-299-301-303\right)\)
=(-6)+(-6)+...+(-6)
=-6x75=-450
1. -2/3 < 0
2. 0,125 > -1/8
3. 3/7 < 11/15
4 -11/6 < -8/9
5 297/16 . 306/25
6 -265/317 < 83/111
chúc bạn học tốt
a) lấy 1 trừ các số đó rồi so sánh( kết quả nào nhỏ hơn thì số đó lớn hơn )
b) so sánh từng số với -1 ( hoặc so sánh số dương trước rồi đảo dấu lại )
c) lấy các số đó từ 1 rồi so sánh bình thường.
d) -265/317 < -83 /111
-5994872.727