Question

If the mean of p and 1/p is M then the mean of p cube and 1/ p cube is

Answer 1

Answer:

p^3 + 1/p^3 = 8M^3 - 6M (ans)

Step-by-step explanation:

Mean of p & 1/p = M

=> (p + 1/p) / 2 = M

=> p + 1/p = 2M

Taking Cube of Both sides

=> (p + 1/p)^3 = (2M)^3

=> p^3 + 1/p^3 + 3 p x 1/p (p + 1/p) = 8M^3

=> p^3 + 1/p^3 + 3 x 2M = 8M^3

=> p^3 + 1/p^3 + 6M = 8M^3

=> p^3 + 1/p^3 = 8M^3 - 6M