The overall term \[Tr+1\] in the binomial extension is given by \[Tr+1\text{ }=\text{ }nCr\text{ }an-r\text{ }br\]
Here\[a\text{ }=\text{ }1\] , \[b\text{ }=\text{ }x\] and \[n\text{ }=\text{ }m\]
Putting the worth
\[Tr+1\text{ }=\text{ }m\text{ }Cr\text{ }1m-r\text{ }xr\]
\[=\text{ }m\text{ }Cr\text{ }xr\]
We need coefficient of \[x2\]
∴ putting \[r\text{ }=2\]
\[T2+1\text{ }=\text{ }mC2\text{ }x2\]
The coefficient of \[x2\text{ }=\text{ }mC2\]
Considering that coefficient of \[x2\text{ }=\text{ }mC2\text{ }=\text{ }6\]
\[\Rightarrow \left( m\text{ }\text{ }1 \right)\text{ }=\text{ }12\]
\[\Rightarrow m2m\text{ }\text{ }12\text{ }=0\]
\[\Rightarrow m24m\text{ }+\text{ }3m\text{ }\text{ }12\text{ }=0\]
\[\Rightarrow \left( m\text{ }\text{ }4 \right)\text{ }+\text{ }3\text{ }\left( m\text{ }\text{ }4 \right)\text{ }=\text{ }0\]
\[\Rightarrow \left( m+3 \right)\text{ }\left( m\text{ }\text{ }4 \right)\text{ }=\text{ }0\]
\[\Rightarrow m\text{ }=\text{ }\text{ }3,\text{ }4\]
We need positive worth of m so \[m\text{ }=\text{ }4\]