Question

Question #cdf3f

Answer 1

`4/sqrt(19)`

Explanation:

Set `u=tan^(-1) (sqrt(3)/4)`, `tanu` must be equal to `sqrt(3)/4`

Hence I must found `cosu`,

After using `cosu=1/sqrt[(tanu)^2+1]` identity, I found,

`cosu=4/sqrt(19)`