Math, asked by ers1, 1 year ago

solve this question this is the question which had in ssc and NDA

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Answers

Answered by Ahmad27
1
Answer to your question is option d - 20
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ers1: hii
Answered by ParamSiddharthMain
0
x = (√6) + (√5).
We have to find x^2 + 1/x^2 - 2.

x^2 + 1/x^2 -2
= x^2 + 1/x^2 -2x(1/x)
= (x - 1/x)^2
= [(x^2 -1)/x]^2
= [(((√6) + (√5))^2)-1)/((√6) + (√5))]^2
= (220 + 40√30)/(11 + 2√30)
= (220 + 40√30)(11 - 2√30)
= 2420 + 440(√30) - 440(√30) - 2400
= 20.

The answer is 20.
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