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If a=5+√3/2 then find the value of a² +1/a² |
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Answer» -step explanation:a= 23+ 5 ∴ A1 = 3+ 5 2 On rationaliging the denominator , we get , a1 = (3+ 5 )(3− 5 )2(3− 5 ) = 9−56−2 5 = 46−2 5 = 23− 5 Also,(a+ a1 ) 2 =a 2 + a 2 1 +2Substituting the VALUES of a= a1 ,We get , `( 23+ 5 + 23− 5 ) 2 =(a 2 + a 2 1 +2)∴a 2 + a 2 1 +2=( 23+ 5 +3− 5 ) 2 =(3) 2 =9∴a 2 + a 2 1 =9−2=7. |
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