x+1/x=4 then x3+1/x3=
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Answered by
6
x+1/x = 4 ---(1)
do the cube both sides
(x+1/x)³=4³
x³ +1/x³ + 3*x*1/x(x+1/x) =64
x³+1/x³+3(x+1/x) =64
x³+1/x³+3*4=64
x³+1/x³+12=64
x³+1/x³= 64-12=52
do the cube both sides
(x+1/x)³=4³
x³ +1/x³ + 3*x*1/x(x+1/x) =64
x³+1/x³+3(x+1/x) =64
x³+1/x³+3*4=64
x³+1/x³+12=64
x³+1/x³= 64-12=52
Answered by
2
x + 1= 4x
4x - x = 1
3x = 1----------(1)
Now
3x +1/3x
putting the value of 3x = 1 in the given equations we get
1+ 1/1
= 2/1
=2 (ANS)
4x - x = 1
3x = 1----------(1)
Now
3x +1/3x
putting the value of 3x = 1 in the given equations we get
1+ 1/1
= 2/1
=2 (ANS)
maria9:
is this x^3 or 3x
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