If `theta_1` and `theta_2` be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip `theta` is given by

Options

A. `tan^(2) delta=tan^(2)delta_(1)+tan^(2)delta_(2)`
B. `cot^(2)delta=cot^(2)delta_(1)+cot^(2)delta_(2)`
C. `tan^(2)delta=(tan^(2)delta_(1)+tan^(2)delta_(2))/(tan^(2)delta_(1)tan^(2)delta_(2))`
D. `cot^(2)delta=1 + cot^(2)delta_(1)cos^(2)delta_(2)`

Answer

B

Explanation

`tan delta_(1)=(V)/(H cos alpha)=(V)/(H tan delta_(1))…(1)`
`tan delta_(2)=(V)/(H sin alpha) rArr sin alpha=(V)/(H tan delta_(2))…(2)`
Squaring and adding Equaitons `(1)` and `(2)`