I think it is 3.4
3 would be the whole
If you get confused by logarithms, here's an easier way to think about this problem: What power of 2 equals 128? Well, we know 2^3 = 8, then 2^4 must equal 16. Doubling every times, we get 2^5 = 32, 2^6 = 64 and 2^7 = 128. So, the value of log₂128 is 7.
2/17 is the lowest term for 6/51
Recall that
d/dx sech(x) = - sech(x) tanh(x)
d/dx tan⁻¹(x) = 1/(1 + x²)
Then by the chain rule,
dy/dx = - sech(x) tanh(x) / (1 + x²)