3. If \( x^{2 / 3}-7 x^{1 / 3}+10=0 \), then \( x= \) (a) \( \{125\} \) (b) \( \{8\} \) (c) \( \phi \) (d) \( \{125,8\} \)

Question

3. If \( x^{2 / 3}-7 x^{1 / 3}+10=0 \), then \( x= \) 

Answer 1

let  x^1/3  = t

t² -7t +10 = 0

(t - 5 ) ( t -2 ) = 0

then t = 5  , t = 2

x^1/3 = 5  then  x= 125

x^1/3 = 2  then  x= 8