Question

If x3 + 1/x3 = m and x2 + 1/2x = 47, find the value of m.​

Answer 1

Hi

x³ + 1/x³ = m

x² + 1/x² = 47

( x + 1/x )² - 2 = 47

( x + 1/x ) =±√49

( x + 1/x ) = ±7

( x + 1/x )³ = ( ±7 )³

x³ + 1/x³ + 3 ( x + 1/x ) = ±343

x³ + 1/x³ + 3 ( ±7 ) = ±343

x³ + 1/x³ = ±343 - ( ±21 )

x³ + 1/x³ = 322

OR

x³ + 1/x³ = -322

So, m can take two values i,e

m = 322 OR m = -322

Answer 2

Answer:

140 underroot 40

Step-by-step explanation: