a. Để pt có nghiệm thì \(\Delta'\ge0\Leftrightarrow2^2-\left(m+1\right)\ge0\Leftrightarrow m\le3\)

b. Theo Viet \(\hept{\begin{cases}x_1+x_2=-4\\x_1x_2=m+1\end{cases}}\)

Lại có \(x_1^2+x_2^2=\left(x_1+x_2\right)^2-2x_1x_2=16-2\left(m+1\right)=14-2m\)

Theo đề bài: 14 - 2m = 10 => m = 2. (TM)

4x37x9+12x18x3+2x45x18=3600 k mk nha dang ha anh!!!!

\(A=2+2^2+2^3+...+2^{2008}\)

\(\Rightarrow2A=2^2+2^3+2^4+...+2^{2009}\)

\(\Rightarrow2A-A=2^{2009}-2\)

\(\Rightarrow A=2^{2009}-2\)

\(\Rightarrow2\left(2^{2009}-2\right)+4=2^{2010}-4+4=2^{2010}=2^{3x}\)

\(\Rightarrow2010=3x\Rightarrow x=670\)

vậy

X x 25=645+255

X x 25=900

       X=900 : 25

       X=36

1+1-2x3+4

k mik nhé

Nếu a=738 thì 8xa+2134 bằng:

8xa+2134

=8x738+2134

=5904+2134

=8038