a/ \(\left(x-23\right):14+25=42-1^{2002}\)
\(\Leftrightarrow\left(x-23\right):14+25=42-1\)
\(\Leftrightarrow\left(x-23\right):14+25=41\)
\(\Leftrightarrow\left(x-23\right):14=16\)
\(\Leftrightarrow x-23=192\)
\(\Leftrightarrow x=215\)
Vậy -
b/ \(2^3.x+2002^0.x=995-15:3\)
\(\Leftrightarrow8.x+1.x=995-5\)
\(\Leftrightarrow x\left(8+1\right)=990\)
\(\Leftrightarrow9x=990\)
\(\Leftrightarrow x=110\)
Vậy ...
b/ \(x+2x+3x+--.+9x=459-3^2\)
\(\Leftrightarrow x\left(1+2+-..+9\right)=459-9\)
\(\Leftrightarrow x.\dfrac{\left(9+1\right).\left[\left(9-1\right):1+1\right]}{2}=450\)
\(\Leftrightarrow x.45=450\)
\(\Leftrightarrow x=10\)
Vậy ...
