Question

x=3-2root2 find xsquare +1/xsquare

Answer 1

Solution:

i ) x = 3-2√2 ----(1)

ii)1/x = 1/(3-2√2)

= (3+2√2)/[(3-2√2)(3+2√2)]

=(3+2√2)/[3²-(2√2)²]

=(3+2√2)/(9-8)

= 3+2√2 ---(2)

iii) x+1/x

= 3-2√2+3+2√2

= 6 ---(3)

iii) x²+1/x²

= (x+1/x)² - 2

= 6² - 2

= 36 - 2

= 34

Therefore,

x²+1/x² = 34

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