Question

( x^{4}+1 / x^{4}=119 )
( Rightarrow x^{4}+1 / x^{4}+2=121 )
( Rightarrowleft(x^{2}+1 / x^{2}right)^{2}=11^{2} )
( Rightarrow x^{2}+1 / x^{2}=11 quad, ) ignore the negative value as ( L H S ) is tve.
( Rightarrow x^{2}+1 / x^{2}-2=9 )
( Rightarrow(x-1 / x)^{2}=3^{2} )
( Rightarrow x-1 / x=+3 ) or -3
( Rightarrow(x-1 / x)^{3}=x^{3}-1 / x^{3}-3 x^{*} 1 / x^{*}(x-1 / x) )
( (+3)^{3}=x^{3}-1 / x^{3}-3(+3) )
Answer: ( quad x^{2}-1 / x^{2}=3^{2}+9 ) or ( -30-9=pm 36 )

# 33 of 25th = 119, find the value of x

Solution