Question

which trigonometric ratio is correct? sina= opp/adj; tana= opp/adj; sina= adj/opp; cosa= opp/hyp

Explanation:

Step1: Recall trigonometric ratios

In a right - triangle, $\sin A=\frac{\text{opposite}}{\text{hypotenuse}}$, $\cos A=\frac{\text{adjacent}}{\text{hypotenuse}}$, and $\tan A=\frac{\text{opposite}}{\text{adjacent}}$.

Step2: Check each option

• For $\sin A=\frac{\text{opp}}{\text{adj}}$: Incorrect, as $\sin A=\frac{\text{opp}}{\text{hyp}}$.
• For $\tan A=\frac{\text{opp}}{\text{adj}}$: Correct.
• For $\sin A=\frac{\text{adj}}{\text{opp}}$: Incorrect, as $\sin A=\frac{\text{opp}}{\text{hyp}}$.
• For $\cos A=\frac{\text{opp}}{\text{hyp}}$: Incorrect, as $\cos A=\frac{\text{adj}}{\text{hyp}}$.

Answer:

B. tanA= opp/adj