if x =7+4√3 find the value of x power2 +1/x power 2
as1432:
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Answered by
5
Given that,
x = 7 + 4√3
So, 1/x = 1/(7 + 4√3)
We rationalize the denominator by multiplying both the numerator and the denominator by (7 - 4√3)
= (7 - 4√3)/{(7 + 4√3)(7 - 4√3)}
= (7 - 4√3)/(49 - 28√3 + 28√3 - 48)
= (7 - 4√3)/1
= 7 - 4√3
So, x + 1/x
= 7 + 4√3 + 7 - 4√3
= 14
∴ x² + 1/x²
= (x + 1/x)² - (2 * x * 1/x)
= 14² - 2
= 196 - 2
= 194
#
Answered by
5
Heya!!
★Answer★
Given,
x=7+4√3
Now,
1/x
={1 / 7+4√3}
={1 × (7-4√3) / (7+4√3) (7-4√3)}
={ (7-4√3) / (7)^2-(4√3)^2 }
={ (7 - 4√3) / (49) - (16×3)}
={ (7-4√3) / (49-48) }
= { (7-4√3) / 1 }
= (7-4√3)
So,
(x+1/x)
=7+4√3+7-4√3 [Cause ,1/x=(7-4√3)]
=14
Now,
(x)^2 +(1/x)^2
=(x+1/x)^2 - 2 × x × 1/x
=(14)^2 - 2 × {(7+4√3)(7-4√3)}
=196 - 2 {(7)^2-(4√3)^2}
=196 - 2 {(49) - (16×3)}
=196 - 2 × 1
=194
So, x+1/x=194
(:
★Answer★
Given,
x=7+4√3
Now,
1/x
={1 / 7+4√3}
={1 × (7-4√3) / (7+4√3) (7-4√3)}
={ (7-4√3) / (7)^2-(4√3)^2 }
={ (7 - 4√3) / (49) - (16×3)}
={ (7-4√3) / (49-48) }
= { (7-4√3) / 1 }
= (7-4√3)
So,
(x+1/x)
=7+4√3+7-4√3 [Cause ,1/x=(7-4√3)]
=14
Now,
(x)^2 +(1/x)^2
=(x+1/x)^2 - 2 × x × 1/x
=(14)^2 - 2 × {(7+4√3)(7-4√3)}
=196 - 2 {(7)^2-(4√3)^2}
=196 - 2 {(49) - (16×3)}
=196 - 2 × 1
=194
So, x+1/x=194
(:
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