Question

4.
If x+ 1 = 7, then the value of X3
1S
х
a) 231
b) 320
d) 233
c) 322​

Answer 1

Step-by-step explanation:

x+1/x =7

(x+1/x)3=x3+1/x3+3(x+1/x)

(7)3=x3+1/x3+3×7

x3+1/x3=343-21

x3+1/x2=322

hence answer is 322