x^2+1/x^2=83 find x^3+1/x^3
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Answered by
7
Hey friend, I hope this will help you nehame
x²+1/x²=83
Subtract 2*x*1/x=2 from both sides
x²+1/x²-2=83-2. (It is the formula (a+b) ²}
(x+1/x) ²=81
x+1/x=√81=9
Then
(x+1/x)³=x³+1/x³+3*x*1/x(x+1/x)
Put the value of (x+1/x) is this
9³=x³+1/x³+3(9)
729=x³+1/x³+27
729-27=x³+1/x³
702=x³+1/x³
My dear it is your answer
Main answer is 702
x²+1/x²=83
Subtract 2*x*1/x=2 from both sides
x²+1/x²-2=83-2. (It is the formula (a+b) ²}
(x+1/x) ²=81
x+1/x=√81=9
Then
(x+1/x)³=x³+1/x³+3*x*1/x(x+1/x)
Put the value of (x+1/x) is this
9³=x³+1/x³+3(9)
729=x³+1/x³+27
729-27=x³+1/x³
702=x³+1/x³
My dear it is your answer
Main answer is 702
Answered by
1
Answer:I am not answering, just replying to abhi569 to the answer given by him to my question, that how u can subtract 2 from RHS. If identity used is (a+b) ^2 the u are wrong, actually question is wrong.
Step-by-step explanation:
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