Vy Thị Hoàng Lan ( Toán Học )
Giới thiệu về bản thân
a,\(119+24+81=\left(119+81\right)+24=200+24=224\)
b,\(57+26+34+63=\left(57+63\right)+\left(26+34\right)=120+60=180\)
c,\(199+36+201+184+37=\left(199+201\right)+\left(36+184\right)+37=400+220+37=657\)d,\(24+36+276=\left(276+24\right)+36=300+36=336\)
e, \(\left(667+11\right)+133=\left(667+133\right)+11=800+11=811\)
f, \(287+121+515+79=\left(287+513\right)+\left(121+79\right)+2=800+200+2=1002\)
g,\(25.104=25\left(100+4\right)=2500+100=2600\)
h,\(8.7.25=\left(4+4\right).7.25=\left(4.25+4.25\right).7=\left(100+100\right).7=200.7=1400\)
i,\(16.6.125=4.4.6.125=4\left(100+25\right).24=\left(400+100\right).24=500.24=12000\)
k,\(48.125.1008=4.12.125.1008=500.12.1008=6000.1008=6000\left(1000+8\right)=6000000+48000=6048000\)
Nội thất
cho mk xin 1 like ạ
\(\dfrac{2^{15}.9^4}{6^6.8^3}=\dfrac{2^{15}.3^8}{2^6.3^6.2^9}=\dfrac{2^{15}}{2^{6+9}}.\dfrac{3^8}{3^6}=3^2=9\)
1.\(\left(-3x+1\right)\times\dfrac{1}{2}=\left(-\dfrac{1}{2}\right)^2\Rightarrow\left(-3x+1\right)=\dfrac{1}{2}\)
\(\Rightarrow\left(-3\right)x=\dfrac{1}{2}-1\Rightarrow x=-\dfrac{1}{2}:\left(-3\right)=\dfrac{1}{6}\)
2.\(x+\dfrac{5}{4}=\dfrac{16}{\left(x+5\right)^2}\Rightarrow x\left(x+5\right)^2+\dfrac{5\left(x+5\right)^2}{4}=16\)
\(4x\left(x+5\right)^2+5\left(x+5\right)^2=64\Rightarrow4x\left(x^2+10x+25\right)+5\left(x^2+10x+25\right)-64=0\)
\(4x^3+40x^2+100x+5x^2+50x+125-64=0\)
\(4x^3+45x^2+150x+61=0\)
\(\Delta=b^2-3ac=45^2-3.4.150=225>1\) vậy phương trình có 1 nghiệm
\(k=\dfrac{9abc-2b^3-27a^2d}{2\sqrt{\left|\Delta\right|^3}}=\dfrac{637}{125}\)
\(x=\dfrac{\sqrt{\Delta}.\left|k\right|}{3ak}.\left(\sqrt[3]{\left|k\right|+\sqrt{k^2+1}}+\sqrt[3]{\left|k\right|-\sqrt{k^2-1}}\right)-\dfrac{b}{3a}=-0,4702284538\)
3.\(\left(x+10\right)^2:\left(-2\right)=\left(-32\right)\Rightarrow\left(x+10\right)^2=16\)
\(\Rightarrow\left\{{}\begin{matrix}x+10=-4\\x+10=4\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=-14\\x=-6\end{matrix}\right.\)
4.\(\left(x+\dfrac{1}{2}\right)\left(x-\dfrac{1}{3}\right)=0\Rightarrow\left\{{}\begin{matrix}x+\dfrac{1}{2}=0\\x-\dfrac{1}{3}=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=-\dfrac{1}{2}\\x=\dfrac{1}{3}\end{matrix}\right.\)
Dãy số trên có số hạng là
\(\left(101-1\right):2+1=51\)
Tổng dãy số trên là
\(\left(1+101\right)\times51:2=2601\)
a, \(49.\left(-17\right)+17.\left(-51\right)=-17\left(49+51\right)\)
\(=-17.100=-1700\)
b, \(37:19+62:19=\left(37+62\right):19=\dfrac{99}{19}\)
c,\(17.\left(-21\right)+35:\left(-7\right)-2.\left(-5\right).\left(-8\right)\)
\(=17.\left(-21\right)+\left(-5\right)-2.\left(-5\right)\left(-8\right)\)
\(=17.\left(-21\right)+\left(-5\right)\left(1+\left(-2\right)\left(-8\right)\right)\)
\(=17\left(-21\right)+\left(-5\right)17=17.\left(-21+-5\right)\)
\(=17.\left(-26\right)=-442\)
a, \(\left(x+67\right)-134=0\Rightarrow x+67=134\)
\(\Rightarrow x=134-67=67\)
b,\(\left(x-213\right)+235=768\Rightarrow x-213=768-235\)
\(\Rightarrow x-213=533\Rightarrow x=746\)
c.sai đầu bài
d, \(x-32:16=48\Rightarrow x-2=48\Rightarrow x=50\)
e, \(\left(x-32\right):16=48\Rightarrow x-32=768\Rightarrow x=800\)
f,\(1428:x=14\Rightarrow x=1428:14=102\)