Question

an element x belongs to 3 period 17 group state no of valence electrons in it,name of the element,name of the family to which it belongs

Answer 1

Then Denominator=2x+1

Fraction =2x+1x

Reciprocal of the fraction =x2x+1

It is given that the sum fo the fraction and its reciprocal is 22116

∴2x+1x+x2x+1=22116

⇒x(2x+1)x2+(2x+1)2=2158⇒2x2+x5x2+4x+1=2158

⇒21(5x2+4x+1)=58(2x2+x)⇒105x2+84x+21=116x

⇒11x2−26x−21=0⇒11x2−33x+7x−21=0⇒11x(x−3)+7(x−3)=0

⇒(11x+7)(x−3)=0⇒x=3,−117

∵ x can not be a negative 

⇒x=3

Hence the fraction =2x+1x=73