## Soil Mechanics- Cohesionless Soil Nphi

Very silly question, but how do we find the angle using calculator. Its a step in a soil mech problem.

2. Relevant equations

The equation is :

Nphi= tan2(45+ θ/2)

given that Nphi= 4.183, the equation becomes

4.183= tan2(45+ θ/2)

How do we calculate this?

Edit: Sorry Mods can you please delete this thread. I figured it out :)