Algebra

[RIO]

x³ +3/x=4(a³+b³) and 3x+3/x³=4(a³-b³) then prove that a²-b²=1

 

[Deleted member 4993]

x³ +3/x=4(a³+b³) and 3x+3/x³=4(a³-b³) then prove that a²-b²=1

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Please share your work/thoughts about this assignment.

 

[RIO]

Sorry I can't solved it but I tried to find the value of a and b then put it in a²-b² but can't solve it

 

[Deleted member 4993]

Sorry I can't solved it but I tried to find the value of a and b then put it in a²-b² but can't solve it

Pleas tell us:

How did you try to "to find the value of a and b" - and what did you get?

 

[RIO]

Please see the attachment

 

[Steven G]

I looked at what you wrote and I did not see any errors. Of course you are not finished as you did not arrive at 1.
I would now try to factor the difference of squares.

 

[Steven G]

Your last line does not seem to equal 1.

 

[Dr.Peterson]

What I tried was cubing both sides of your equation (which looked right to me, after a quick comparison with my own previous attempt).

It didn't come out to 1 for me, either, but I probably made a mistake.