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Grade 11Algebra

x+1/x =1 ,
x2+1/x2 =2
and x3+1/x3=3
then x5 + 1/x5 = what

Profile image of ankit raj
10 Years agoGrade 11
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8 Answers

Profile image of Anoopam Mishra
10 Years ago
(x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) = x^5 + \frac{1}{x^5} + x + \frac{1}{x}
=> x^5 + \frac{1}{x^5} = (x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) - (x + \frac{1}{x} )
=> x^5 + \frac{1}{x^5} = (2)(3) - 1
=> x^5 + \frac{1}{x^5} = 5
Profile image of HARINATH
10 Years ago
5
Profile image of pa1
10 Years ago
5
Profile image of RAJU
10 Years ago
5
Profile image of SEELA YUVARAJU
10 Years ago
5
Profile image of Raghu Vamshi Hemadri
10 Years ago
=> x^5 + \frac{1}{x^5} = (x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) - (x + \frac{1}{x} )=> x^5 + \frac{1}{x^5} = (x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) - (x + \frac{1}{x} )
=> x^5 + \frac{1}{x^5} = (2)(3) - 1
=> x^5 + \frac{1}{x^5} = 5
Profile image of SHANMUKESHWAR
10 Years ago
5
Profile image of RAGHU
10 Years ago
 
=> x^5 + \frac{1}{x^5} = (x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) - (x + \frac{1}{x} )=> x^5 + \frac{1}{x^5} = (x^2 + \frac{1}{x^2})(x^3 + \frac{1}{x^3}) - (x + \frac{1}{x} )
=> x^5 + \frac{1}{x^5} = (2)(3) - 1
=> x^5 + \frac{1}{x^5} = 5