Question

If x is not equal to 0and 3x+1/3x=8;find the value of :27x3+1/27x3

Answer 1

Answer:

488

Step-by-step explanation:

3x+1/3x=8

Cubing both sides

(3x+1/3x)^3=(8)^3

27x3+1/27x3+3(3x)(1/3x)(3x+1/3x)=512    ...(using the identity:(a+b)^3)

27x3+1/27x3+3(8)=512                           ...(3x*1/3x=1, 3x+1/3x=8)

27x3+1/27x3+24=512

27x3+1/27x3=512-24

27x3+1/27x3=488

I hope it is helpful for you...