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3 years ago

If x+1/x=7,find x^2+1/x^2

Mathematics

1 answer:

trapecia [35]3 years ago

3 0

Answer:

x²+1/x² = 51

Explanation:

Given x - 1/x = 7 ---(1)

We know the algebraic identity:

a²+b²-2ab = (a-b)²

a²+b² = (a-b)²+2ab

Now,

x²+1/x²

= (x-1/x)²+2*x*(1/x)

= (x-1/x)²+2

:7²+2 [ from (1)] =

= 49+2

= 51

Therefore,

x²+1/x² = 51

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answer
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If x+1/x=7,find x^2+1/x^2​

If x+1/x=7,find x^2+1/x^2