using binomial theorem determine whch number is larger 1.2^4000 or 800?
We have,
(1.2)4000 = (1+0.2)4000
Now, expanding by binomial theorem, we get
(1+0.2) 4000 = 4000C0 (1)4000 (0.2)0 + 4000C1 (1)4000-1 (0.2)1 + 4000C2 (1)4000-2 (0.2)2 + other terms of the expansion
= 1 + 4000 × (0.2) + other terms of the expansion
= 1 + 800 + other terms of the expansion
= 801 + other terms of the expansion
Hence, (1.2)4000 > 800