**Known values:**

Full dip direction = *α*

Apparent dip direction = *β*

Apparent dip rate = *1 in y (AC = y)*

*Solution:*

Full dip rate = *1 in x (AB = x)*

In triangle ABC:

i.e.

i.e.

cot full dip (1 in x) = cot apparent dip (1 in y) X cosine angle between full dip and apparent dip (β-α)