help with expansion

[frozen trench]

Help with Q14 pls algebra expansion is eating my head #help-school

[worn flume]

@frozen trench x-1/x=5 can you solve for x? is not that hard. Step1 multiply both parts by x then you have x²-1=5x → x²-5x-1=0 can you solve this ?

[torpid meteor]

(i) x-(1/x) = 5
(x-(1/x))² = 25
x²+(1/x²)-2 = 25
x²+(1/x²) = 27
2(x²+(1/x²)) = 54
2x²+(2/x²) = 54
(ii) (x-(1/x))³ = 125
x³-3x+(3/x)-(1/x³) = 125
x³-(1/x³)-3x+(3/x) = 125
x³-(1/x³)-3(x-(1/x)) = 125
x³-(1/x³)-3(5) = 125
x³-(1/x³)-15 = 125
x³-(1/x³) = 140
5(x³-(1/x³)) = 700
5x³-(5/x³) = 700
5x³-(5/x³)-(2x²+(2/x²)) = 700-54
5x³-(5/x³)-2x²-(2/x²) = 646
5x³-2x²-(2/x²)-(5/x³) = 646

[modest sable]

What does Derick sir mean?

And why is it all over your paper?

[frozen trench]

well i go to educare math classes and the main math professor there is derrick sir hes a damn math prodigy

@everyone thx for the help really appreciate it

[frozen trench]

bro btw thx for typing all that for me

[wary shore]

@frozen trench has given 1 rep to @torpid meteor

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