Question

answer my question



get brainlist point also

Answer 1

a^2 =7+4√3
1/a^2=1/7+4√3. ( by rationalising the denominator we will get)
7-4√3
Now,a^2+1/a^2
=7+4√3+7-4√3
=14 ans.
plz mark me as brainliest i need

Answer 2

Given,

a = 2 + √3.

So, 1 / a = 1 / ( 2 + √3 )

To rationalize the denominator , multiply the numerator and denominator by ( 2 - √3 ).

 1/ a = 1( 2 - √3 ) / ( 2+ √3 ) ( 2 - √3 )

 1 / a = ( 2 - √3 ) / { ( 2 )^2 - ( √3 )^2 }    [ ( a+b)(a-b)=a^2 - b^2 ]

 1 / a = ( 2 - √3 ) / ( 4 - 3 )

 1 / a = ( 2 - √3 ) / 1 = ( 2 - √3 ).

Now,

 = a^2 + ( 1 / a )^2

By substituting the values of a and 1 / a ,

 = ( 2 + √3 )^2 + ( 2 - √3 )^2

 = ( 2)^2 + (√3 )^2 + 2 * 2 * √3 + ( 2 )^2 + ( √3 )^2 - 2* 2 * √3

 = 4 + 3 + 4√3 + 4 + 3 - 4√3

 = 7 + 7

 = 14.

So, your final answer is 14.