Find the value of $\tan 45^{\circ }$.

Step-by-step solution

1. Recall that $\tan \theta =\frac{\text{opposite side}}{\text{adjacent side}}$ in a right–angled triangle.
2. In a $45^{\circ }-45^{\circ }-90^{\circ }$ triangle the two legs are equal.
3. Hence the opposite side equals the adjacent side, so their ratio is $1$.
4. Therefore $\tan 45^{\circ }=1$.

Concept tested: Basic trigonometric value

Published 25 August 2026 · How this solution was prepared and checked

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