Sigma bond is stronger than Pi bond because of the following reasons:

1. The extent of overlapping in Sigma bond is greater than in Pi bond.
2. The electron density in intermolecular axis is more in Sigma bond than in Pi bond.
3. There is free rotation of atom about Sigma bond but not about Pi bond.

Log_2aa=x    then, a=(2a)^x  ......(1)

Log_3a2a=y    then,2a=(3a)^y ......(2)

Log_4a 3a=z  then, 3a=(4a)^z ......(3)

So, 

a=(2a)^x  [from (1)]

Or, a=(3a)^xy    [from(2)]

Or, a=(4a)^xyz     [from(3)]

Multiplying both sides by 4a,

4a.a=4a.(4a)^xyz  

Or,(2a)² =(4a)^{xyz + 1} 

Or,(3a)^2y =(4a)^xyz+1 

Or,(4a)^2yz =(4a)^xyz+1 

Or, 2yz = xyz+1 .proved.

सेवाहरूमा नैतिकता, मनोविजञान, फिजियोलोजी, मानवविजञान अनतरगत सामाजिक अधययनको पराथमिक उददेशय युवाहरूलाई जानकारी र कारण पुरयाउन मददत गरनु हो I सामाजिक अधययन विजञानको शाखा हो जुन समाज र वयकतिहरू बीचको समबनधको अधययनमा समरपित छ I सामाजिक अधययन पहिले समाजको मौलिक विजञान र समाजशासतरको कषेतरलाई सनदरभ गरन परयोग गरिएको थियो I समाजशासतर बाहेक अब सामाजिक अधययनले 

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