a+1/a = 3 হলে a4 + (1/a)4 = কত?

a+1/a = 3 হলে a⁴ + (1/a)⁴ = কত?

A 27

B 47

C 49

D 51

Solution

Correct Answer: Option B

a4 + (1/a)4

=(a2)2-(1/a2)2

=(a2+1/a2)2-2a2.1/a2

={(a+1/a)2-2a.1/a}-2 =(32-2)2-2

=49-2=47