Q. If the variables \( n, r \in I \) in the expansion of \( (1+x)^{n} \) Satisfies the condition \( n^{2}-4 n r-n+4 r^{2}-2=0(r \leqslant \) \( n) \) than the value of \( y \) in expression given below is \( \log _{10}\left(a^{r-1}+a^{r+1}\right)=0.2+\log _{10}\left(y \cdot a^{r}\right) \) where \( a^{z}(z \in I) \) denotes coefficient of \( x^{z} \) in exp of \( (1+x)^{n} \) (Take \( \log 3=0.4 \) )
