\(54^2+44^2-54\cdot88=54^2-2\cdot44\cdot54+44^2=\left(54-44\right)^2=10^2=100\)

1234^8×56743²⁷ = 1.21942e+153 nha bạn 

HT

Ta có

\(n-24⋮77\) => n-24 đồng thời chia hết cho 7 và 11

\(n-24⋮7\Rightarrow\left(n-3\right)-21⋮7\Rightarrow n-3⋮7\Rightarrow a=3\)

\(n-24⋮11\Rightarrow\left(n-2\right)-22⋮11\Rightarrow n-2⋮11\Rightarrow b=2\)

\(\Rightarrow a+b=3+2=5\)

TL

x=2

HT

\(x+3=\left(x+3\right)^2\)

\(\Rightarrow\left(x+3\right)+\left(3+x\right)^2=0\)

\(\Rightarrow\left(x+3\right)+\left(x+3\right)\)

\(\Rightarrow\left(x+3\right)\left(1+x+3\right)=0\)

\(\Rightarrow\left(x+3\right)\left(x+2\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x+3=0\\x+2=0\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=3\\x=2\end{cases}}\)

bài 1

a) 2003.2005=(2004-1).(2004+1)=\(2004^2\)-1 (\(1\))

  \(2004^2\)(2)

từ 1 và 2 => 2003.2005<\(2004^2\)

b)....

Bài 2

2015.2017=(2016-1).(2016+1)=\(2016^2\)-1  (1)

\(2016^2\)(2)

từ 1 và 2 => \(2016^2\)> 2015.2017=> A>B

\(E=\left(x^2y+y^3\right)\left(x^3+xy^2\right)-xy\left(x^4+y^4\right)\)

\(=\left(x^5y+x^3y^3+x^3y^3+y^5\right)-xy^5-x^5y\)

\(=x^5y+x^3y^3+x^3y^3+xy^5-xy^5-x^5y\)

\(=2x^3y^3\)

\(\left(1+x+x^2\right)\left(1-x\right)\left(1+x\right)\left(1-x+x^2\right)\)

\(=\left(1-x^3\right)\left(1+x^3\right)\)

\(=1+x^3-x^3-x^6\)

\(=1-x^6\)

cần gấp mong mn giúp đỡ