Prove that 3sin⁡π6sec⁡π3−4sin⁡5π6cot⁡π4=13 \sin \frac{\pi}{6} \sec \frac{\pi}{3}-4 \sin \frac{5 \pi}{6} \cot \frac{\pi}{4}=1

Answer: The given equation is proven to be true, as the left-hand side simplifies to 1.

Step-by-step solution

Step 1: Evaluate individual trigonometric values

First, we need to find the values of each trigonometric function in the given expression. We know that π6\frac{\pi}{6} radians is equal to 30∘30^\circ, π3\frac{\pi}{3} radians is equal to 60∘60^\circ, and π4\frac{\pi}{4} radians is equal to 45∘45^\circ. For sin⁡5π6\sin \frac{5\pi}{6}, we use the identity sin⁡(π−x)=sin⁡x\sin(\pi - x) = \sin x.

Step 2: Substitute the values into the expression

Now, substitute the calculated trigonometric values back into the left-hand side of the given equation. This will allow us to simplify the expression.

Step 3: Simplify the expression

Perform the multiplications in each term. In the first term, 3×12×23 \times \frac{1}{2} \times 2 simplifies to 3×1=33 \times 1 = 3. In the second term, 4×12×14 \times \frac{1}{2} \times 1 simplifies to 2×1=22 \times 1 = 2.

Step 4: Calculate the final result

Finally, subtract the second term from the first term to get the final result. The result is 3−2=13 - 2 = 1. Since this matches the right-hand side of the original equation, the identity is proven.

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