Shown that : `tan48^(@)tan23^(@)tan42^(@)tan67^(@)=1`

Explanation

To show that \( \tan 48^\circ \tan 23^\circ \tan 42^\circ \tan 67^\circ = 1 \), we can use the properties of complementary angles in trigonometry.

### Step-by-step Solution:

1. **Understanding Complementary Angles**:
- Recall that two angles are complementary if their sum is \( 90^\circ \). Thus, we can use the identity \( \tan(90^\circ - \theta) = \cot(\theta) \).

2. **Rewriting the Angles**:
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