Question

If x to the power 4 + 1 by x to the power 4 equal to 47 find the value of x cube + 1 by x cube

Answer 1

Answer:

18

Step-by-step explanation:

x⁴+1/x⁴=47

(x²+1/x²)²=x⁴+1/x⁴+2(x²)(1/x²)

(x²+1/x²)²=47+2=49

x²+1/x²=√49

x²+1/x²=7

(x+1/x)²=x²+1/x²+2(x)(1/x)

(x+1/x)²=7+2=9

x+1/x=√9

x+1/x=3

x³+1/x³=(x+1/x)(x²+1/x²-(x)(1/x))

x³+1/x³=(3)(7-1)

x³+1/x³=3(6)

x³+1/x³=18